| Network Working Group | Q. Wu, Ed. |
| Internet-Draft | Huawei |
| Obsoletes: 8049 (if approved) | S. Litkowski |
| Intended status: Standards Track | Orange |
| Expires: June 7, 2018 | L. Tomotaki |
| Verizon | |
| K. Ogaki | |
| KDDI Corporation | |
| December 4, 2017 |
YANG Data Model for L3VPN Service Delivery
draft-wu-l3sm-rfc8049bis-10
This document defines a YANG data model that can be used for communication between customers and network operators and to deliver a Layer 3 provider-provisioned VPN service. This document is limited to BGP PE-based VPNs as described in RFCs 4026, 4110, and 4364. This model is intended to be instantiated at the management system to deliver the overall service. It is not a configuration model to be used directly on network elements. This model provides an abstracted view of the Layer 3 IP VPN service configuration components. It will be up to the management system to take this model as input and use specific configuration models to configure the different network elements to deliver the service. How the configuration of network elements is done is out of scope for this document.
This document obsoletes RFC 8049 to replace the unimplementable module in that RFC with a new module with the same name that is not backward compatible. The changes are a series of small fixes to the YANG module, and some clarifications to the text.
This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet-Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress."
This Internet-Draft will expire on June 7, 2018.
Copyright (c) 2017 IETF Trust and the persons identified as the document authors. All rights reserved.
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This document defines a Layer 3 VPN service data model written in YANG. The model defines service configuration elements that can be used in communication protocols between customers and network operators. Those elements can also be used as input to automated control and configuration applications.
The YANG module described in [RFC8049] cannot be implemented because of issues around the use of XPATH. These issues are explained in Section 1.4.1.
This document obsoletes [RFC8049] by creating a new module with the same name as the module defined in [RFC8049]. The changes from [RFC8049] are listed in full in Section 1.4. They are small in scope, but include fixes to the module to make it possible to implement.
Section 11 of [RFC7950] describes when it is permissible to re-use a module name. Section 1.4.2 provides an impact assessment in this context.
The following terms are defined in [RFC6241] and are not redefined here:
The following terms are defined in [RFC7950] and are not redefined here:
The terminology for describing YANG data models is found in [RFC7950].
This document presents some configuration examples using XML representation.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.
A simplified graphical representation of the data model is presented in Section 6.
The meanings of the symbols in these diagrams are as follows:
This document revises and obsoletes L3VPN Service Model [RFC8049] , drawing on insights gained from L3VPN Service Model deployments and on feedback from the community. The major changes are:
[RFC8049] made an initial attempt to define a YANG model for L3VPN services. After it was published it was discovered that, while the YANG compiled it was broken from an implementation perspective. That is, it was impossible to build a functional implementation of the module.
Section 1.4 provides a full list of the changes since [RFC8049]. Some of these changes remove ambiguities from the documented YANG, while other changes fix the implementation issues.
When changing the content of a YANG module, care must be taken to ensure that there are no interoperability issues caused by a failure to enable backward compatibility.
Section 11 of [RFC7950] clearly describes the circumstances under which it is not acceptable to maintain a module name.
The module defined in this document is not backward compatible with that defined in [RFC8049], but it is important to understand that there is no possibility of an interoperability issue between the module defined in this document and that presented in [RFC8049] because that module could not be implemented for the reasons described in Section 1.4.1. Thus, noting the rules set out in RFC7950, it was decided to retain the module name in this document.
AAA: Authentication, Authorization, and Accounting.
ACL: Access Control List.
ADSL: Asymmetric DSL.
AH: Authentication Header.
AS: Autonomous System.
ASBR: Autonomous System Border Router.
ASM: Any-Source Multicast.
BAS: Broadband Access Switch.
BFD: Bidirectional Forwarding Detection.
BGP: Border Gateway Protocol.
BSR: Bootstrap Router.
CE: Customer Edge.
CLI: Command Line Interface.
CsC: Carriers' Carriers.
CSP: Cloud Service Provider.
DHCP: Dynamic Host Configuration Protocol.
DSLAM: Digital Subscriber Line Access Multiplexer.
ESP: Encapsulating Security Payload.
GRE: Generic Routing Encapsulation.
IGMP: Internet Group Management Protocol.
LAN: Local Area Network.
MLD: Multicast Listener Discovery.
MTU: Maximum Transmission Unit.
NAT: Network Address Translation.
NETCONF: Network Configuration Protocol.
NNI: Network-to-Network Interface.
OAM: Operations, Administration, and Maintenance.
OSPF: Open Shortest Path First.
OSS: Operations Support System.
PE: Provider Edge.
PIM: Protocol Independent Multicast.
POP: Point of Presence.
QoS: Quality of Service.
RD: Route Distinguisher.
RIP: Routing Information Protocol.
RP: Rendezvous Point.
RT: Route Target.
SFTP: Secure FTP.
SLA: Service Level Agreement.
SLAAC: Stateless Address Autoconfiguration.
SP: Service Provider.
SPT: Shortest Path Tree.
SSM: Source-Specific Multicast.
VM: Virtual Machine.
VPN: Virtual Private Network.
VRF: VPN Routing and Forwarding.
VRRP: Virtual Router Redundancy Protocol.
Customer Edge (CE) Device: A CE is equipment dedicated to a particular customer; it is directly connected (at Layer 3) to one or more PE devices via attachment circuits. A CE is usually located at the customer premises and is usually dedicated to a single VPN, although it may support multiple VPNs if each one has separate attachment circuits.
Provider Edge (PE) Device: A PE is equipment managed by the SP; it can support multiple VPNs for different customers and is directly connected (at Layer 3) to one or more CE devices via attachment circuits. A PE is usually located at an SP point of presence (POP) and is managed by the SP.
PE-Based VPNs: The PE devices know that certain traffic is VPN traffic. They forward the traffic (through tunnels) based on the destination IP address of the packet and, optionally, based on other information in the IP header of the packet. The PE devices are themselves the tunnel endpoints. The tunnels may make use of various encapsulations to send traffic over the SP network (such as, but not restricted to, GRE, IP-in-IP, IPsec, or MPLS tunnels).
A Layer 3 IP VPN service is a collection of sites that are authorized to exchange traffic between each other over a shared IP infrastructure. This Layer 3 VPN service model aims at providing a common understanding of how the corresponding IP VPN service is to be deployed over the shared infrastructure. This service model is limited to BGP PE-based VPNs as described in [RFC4026], [RFC4110], and [RFC4364].
l3vpn-svc | Model | | +------------------+
+-----+ | Orchestration | < --- > | OSS | +------------------+
+-----+ | | +----------------+ | | Config manager | |
+----------------+ | | | | NETCONF/CLI ... | |
+------------------------------------------------+ Network +++++++ +
AAA + +++++++ ++++++++ Bearer ++++++++ ++++++++ ++++++++ + CE A +
----------- + PE A + + PE B + ---- + CE B + ++++++++ Connection
++++++++ ++++++++ ++++++++ Site A Site B
The idea of the L3 IP VPN service model is to propose an abstracted interface between customers and network operators to manage configuration of components of an L3VPN service. The model is intended to be used in a mode where the network operator's system is the server and the customer's system is the client. A typical scenario would be to use this model as an input for an orchestration layer that will be responsible for translating it to an orchestrated configuration of network elements that will be part of the service. The network elements can be routers but can also be servers (like AAA); the network's configuration is not limited to these examples. The configuration of network elements can be done via the CLI, NETCONF/RESTCONF [RFC6241] [RFC8040] coupled with YANG data models of a specific configuration (BGP, VRF, BFD, etc.), or some other technique, as preferred by the operator.
The usage of this service model is not limited to this example; it can be used by any component of the management system but not directly by network elements.
The YANG module is divided into two main containers: "vpn-services" and "sites".
The "vpn-service" list under the vpn-services container defines global parameters for the VPN service for a specific customer.
A "site" is composed of at least one "site-network-access" and, in the case of multihoming, may have multiple site-network-access points. The site-network-access attachment is done through a "bearer" with an "ip-connection" on top. The bearer refers to properties of the attachment that are below Layer 3, while the connection refers to properties oriented to the Layer 3 protocol. The bearer may be allocated dynamically by the SP, and the customer may provide some constraints or parameters to drive the placement of the access.
Authorization of traffic exchange is done through what we call a VPN policy or VPN service topology defining routing exchange rules between sites.
The figure below describes the overall structure of the YANG module:
module: ietf-l3vpn-svc +--rw l3vpn-svc +--rw
vpn-profiles | +--rw valid-provider-identifiers | +--rw
cloud-identifier* [id] {cloud-access}? | | +--rw id string | +--rw
encryption-profile-identifier* [id] | | +--rw id string | +--rw
qos-profile-identifier* [id] | | +--rw id string | +--rw
bfd-profile-identifier* [id] | +--rw id string +--rw vpn-services |
+--rw vpn-service* [vpn-id] | +--rw vpn-id svc-id | +--rw
customer-name? string | +--rw vpn-service-topology? identityref |
+--rw cloud-accesses {cloud-access}? | | +--rw cloud-access*
[cloud-identifier] | | +--rw cloud-identifier ->
/l3vpn-svc/vpn-profiles/valid-provider-identifiers/cloud-identifier/id
| | +--rw (list-flavor)? | | | +--:(permit-any) | | | | +--rw
permit-any? empty | | | +--:(deny-any-except) | | | | +--rw
permit-site* -> /l3vpn-svc/sites/site/site-id | | |
+--:(permit-any-except) | | | +--rw deny-site* ->
/l3vpn-svc/sites/site/site-id | | +--rw address-translation | | +--rw
nat44 | | +--rw enabled? boolean | | +--rw nat44-customer-address?
inet:ipv4-address | +--rw multicast {multicast}? | | +--rw enabled?
boolean | | +--rw customer-tree-flavors | | | +--rw tree-flavor*
identityref | | +--rw rp | | +--rw rp-group-mappings | | | +--rw
rp-group-mapping* [id] | | | +--rw id uint16 | | | +--rw
provider-managed | | | | +--rw enabled? boolean | | | | +--rw
rp-redundancy? boolean | | | | +--rw optimal-traffic-delivery? boolean
| | | +--rw rp-address inet:ip-address | | | +--rw groups | | | +--rw
group* [id] | | | +--rw id uint16 | | | +--rw (group-format) | | |
+--:(singleaddress) | | | | +--rw group-address? inet:ip-address | | |
+--:(startend) | | | +--rw group-start? inet:ip-address | | | +--rw
group-end? inet:ip-address | | +--rw rp-discovery | | +--rw
rp-discovery-type? identityref | | +--rw bsr-candidates | | +--rw
bsr-candidate-address* inet:ip-address | +--rw carrierscarrier?
boolean {carrierscarrier}? | +--rw extranet-vpns {extranet-vpn}? |
+--rw extranet-vpn* [vpn-id] | +--rw vpn-id svc-id | +--rw
local-sites-role? identityref +--rw sites +--rw site* [site-id] +--rw
site-id svc-id +--rw requested-site-start? yang:date-and-time +--rw
requested-site-stop? yang:date-and-time +--rw locations | +--rw
location* [location-id] | +--rw location-id svc-id | +--rw address?
string | +--rw postal-code? string | +--rw state? string | +--rw city?
string | +--rw country-code? string +--rw devices | +--rw device*
[device-id] | +--rw device-id svc-id | +--rw location ->
../../../locations/location/location-id | +--rw management | +--rw
address-family? address-family | +--rw address? inet:ip-address +--rw
site-diversity {site-diversity}? | +--rw groups | +--rw group*
[group-id] | +--rw group-id string +--rw management | +--rw type
identityref +--rw vpn-policies | +--rw vpn-policy* [vpn-policy-id] |
+--rw vpn-policy-id svc-id | +--rw entries* [id] | +--rw id svc-id |
+--rw filters | | +--rw filter* [type] | | +--rw type identityref | |
+--rw lan-tag* string {lan-tag}? | | +--rw ipv4-lan-prefix*
inet:ipv4-prefix {ipv4}? | | +--rw ipv6-lan-prefix* inet:ipv6-prefix
{ipv6}? | +--rw vpn* [vpn-id] | +--rw vpn-id ->
/l3vpn-svc/vpn-services/vpn-service/vpn-id | +--rw site-role?
identityref +--rw site-vpn-flavor? identityref +--rw maximum-routes |
+--rw address-family* [af] | +--rw af address-family | +--rw
maximum-routes? uint32 +--rw security | +--rw authentication | +--rw
encryption {encryption}? | +--rw enabled? boolean | +--rw layer?
enumeration | +--rw encryption-profile | +--rw (profile)? |
+--:(provider-profile) | | +--rw profile-name? ->
/l3vpn-svc/vpn-profiles/valid-provider-identifiers/encryption-profile-identifier/id
| +--:(customer-profile) | +--rw algorithm? string | +--rw (key-type)?
| +--:(psk) | +--rw preshared-key? string +--rw service | +--rw qos
{qos}? | | +--rw qos-classification-policy | | | +--rw rule* [id] | |
| +--rw id string | | | +--rw (match-type)? | | | | +--:(match-flow) |
| | | | +--rw match-flow | | | | | +--rw dscp? inet:dscp | | | | |
+--rw dot1p? uint8 | | | | | +--rw ipv4-src-prefix? inet:ipv4-prefix |
| | | | +--rw ipv6-src-prefix? inet:ipv6-prefix | | | | | +--rw
ipv4-dst-prefix? inet:ipv4-prefix | | | | | +--rw ipv6-dst-prefix?
inet:ipv6-prefix | | | | | +--rw l4-src-port? inet:port-number | | | |
| +--rw target-sites* svc-id {target-sites}? | | | | | +--rw
l4-src-port-range | | | | | | +--rw lower-port? inet:port-number | | |
| | | +--rw upper-port? inet:port-number | | | | | +--rw l4-dst-port?
inet:port-number | | | | | +--rw l4-dst-port-range | | | | | | +--rw
lower-port? inet:port-number | | | | | | +--rw upper-port?
inet:port-number | | | | | +--rw protocol-field? union | | | |
+--:(match-application) | | | | +--rw match-application? identityref |
| | +--rw target-class-id? string | | +--rw qos-profile | | +--rw
(qos-profile)? | | +--:(standard) | | | +--rw profile? ->
/l3vpn-svc/vpn-profiles/valid-provider-identifiers/qos-profile-identifier/id
| | +--:(custom) | | +--rw classes {qos-custom}? | | +--rw class*
[class-id] | | +--rw class-id string | | +--rw direction? identityref
| | +--rw rate-limit? decimal64 | | +--rw latency | | | +--rw
(flavor)? | | | +--:(lowest) | | | | +--rw use-lowest-latency? empty |
| | +--:(boundary) | | | +--rw latency-boundary? uint16 | | +--rw
jitter | | | +--rw (flavor)? | | | +--:(lowest) | | | | +--rw
use-lowest-jitter? empty | | | +--:(boundary) | | | +--rw
latency-boundary? uint32 | | +--rw bandwidth | | +--rw
guaranteed-bw-percent decimal64 | | +--rw end-to-end? empty | +--rw
carrierscarrier {carrierscarrier}? | | +--rw signalling-type?
enumeration | +--rw multicast {multicast}? | +--rw
multicast-site-type? enumeration | +--rw multicast-address-family | |
+--rw ipv4? boolean {ipv4}? | | +--rw ipv6? boolean {ipv6}? | +--rw
protocol-type? enumeration +--rw traffic-protection {fast-reroute}? |
+--rw enabled? boolean +--rw routing-protocols | +--rw
routing-protocol* [type] | +--rw type identityref | +--rw ospf
{rtg-ospf}? | | +--rw address-family* address-family | | +--rw
area-address yang:dotted-quad | | +--rw metric? uint16 | | +--rw
sham-links {rtg-ospf-sham-link}? | | +--rw sham-link* [target-site] |
| +--rw target-site svc-id | | +--rw metric? uint16 | +--rw bgp
{rtg-bgp}? | | +--rw autonomous-system uint32 | | +--rw
address-family* address-family | +--rw static | | +--rw
cascaded-lan-prefixes | | +--rw ipv4-lan-prefixes* [lan next-hop]
{ipv4}? | | | +--rw lan inet:ipv4-prefix | | | +--rw lan-tag? string |
| | +--rw next-hop inet:ipv4-address | | +--rw ipv6-lan-prefixes* [lan
next-hop] {ipv6}? | | +--rw lan inet:ipv6-prefix | | +--rw lan-tag?
string | | +--rw next-hop inet:ipv6-address | +--rw rip {rtg-rip}? | |
+--rw address-family* address-family | +--rw vrrp {rtg-vrrp}? | +--rw
address-family* address-family +--ro actual-site-start?
yang:date-and-time +--ro actual-site-stop? yang:date-and-time +--rw
site-network-accesses +--rw site-network-access*
[site-network-access-id] +--rw site-network-access-id svc-id +--rw
site-network-access-type? identityref +--rw (location-flavor) |
+--:(location) | | +--rw location-reference? ->
../../../locations/location/location-id | +--:(device) | +--rw
device-reference? -> ../../../devices/device/device-id +--rw
access-diversity {site-diversity}? | +--rw groups | | +--rw group*
[group-id] | | +--rw group-id string | +--rw constraints | +--rw
constraint* [constraint-type] | +--rw constraint-type identityref |
+--rw target | +--rw (target-flavor)? | +--:(id) | | +--rw group*
[group-id] | | +--rw group-id string | +--:(all-accesses) | | +--rw
all-other-accesses? empty | +--:(all-groups) | +--rw all-other-groups?
empty +--rw bearer | +--rw requested-type {requested-type}? | | +--rw
requested-type? string | | +--rw strict? boolean | +--rw always-on?
boolean {always-on}? | +--rw bearer-reference? string
{bearer-reference}? +--rw ip-connection | +--rw ipv4 {ipv4}? | | +--rw
address-allocation-type? identityref | | +--rw provider-dhcp | | |
+--rw provider-address? inet:ipv4-address | | | +--rw prefix-length?
uint8 | | | +--rw (address-assign)? | | | +--:(number) | | | | +--rw
number-of-dynamic-address? uint16 | | | +--:(explicit) | | | +--rw
customer-addresses | | | +--rw address-group* [group-id] | | | +--rw
group-id string | | | +--rw start-address? inet:ipv4-address | | |
+--rw end-address? inet:ipv4-address | | +--rw dhcp-relay | | | +--rw
provider-address? inet:ipv4-address | | | +--rw prefix-length? uint8 |
| | +--rw customer-dhcp-servers | | | +--rw server-ip-address*
inet:ipv4-address | | +--rw addresses | | +--rw provider-address?
inet:ipv4-address | | +--rw customer-address? inet:ipv4-address | |
+--rw prefix-length? uint8 | +--rw ipv6 {ipv6}? | | +--rw
address-allocation-type? identityref | | +--rw provider-dhcp | | |
+--rw provider-address? inet:ipv6-address | | | +--rw prefix-length?
uint8 | | | +--rw (address-assign)? | | | +--:(number) | | | | +--rw
number-of-dynamic-address? uint16 | | | +--:(explicit) | | | +--rw
customer-addresses | | | +--rw address-group* [group-id] | | | +--rw
group-id string | | | +--rw start-address? inet:ipv6-address | | |
+--rw end-address? inet:ipv6-address | | +--rw dhcp-relay | | | +--rw
provider-address? inet:ipv6-address | | | +--rw prefix-length? uint8 |
| | +--rw customer-dhcp-servers | | | +--rw server-ip-address*
inet:ipv6-address | | +--rw addresses | | +--rw provider-address?
inet:ipv6-address | | +--rw customer-address? inet:ipv6-address | |
+--rw prefix-length? uint8 | +--rw oam | +--rw bfd {bfd}? | +--rw
enabled? boolean | +--rw (holdtime)? | +--:(fixed) | | +--rw
fixed-value? uint32 | +--:(profile) | +--rw profile-name? ->
/l3vpn-svc/vpn-profiles/valid-provider-identifiers/bfd-profile-identifier/id
+--rw security | +--rw authentication | +--rw encryption {encryption}?
| +--rw enabled? boolean | +--rw layer? enumeration | +--rw
encryption-profile | +--rw (profile)? | +--:(provider-profile) | |
+--rw profile-name? ->
/l3vpn-svc/vpn-profiles/valid-provider-identifiers/encryption-profile-identifier/id
| +--:(customer-profile) | +--rw algorithm? string | +--rw (key-type)?
| +--:(psk) | +--rw preshared-key? string +--rw service | +--rw
svc-input-bandwidth uint64 | +--rw svc-output-bandwidth uint64 | +--rw
svc-mtu uint16 | +--rw qos {qos}? | | +--rw qos-classification-policy
| | | +--rw rule* [id] | | | +--rw id string | | | +--rw (match-type)?
| | | | +--:(match-flow) | | | | | +--rw match-flow | | | | | +--rw
dscp? inet:dscp | | | | | +--rw dot1p? uint8 | | | | | +--rw
ipv4-src-prefix? inet:ipv4-prefix | | | | | +--rw ipv6-src-prefix?
inet:ipv6-prefix | | | | | +--rw ipv4-dst-prefix? inet:ipv4-prefix | |
| | | +--rw ipv6-dst-prefix? inet:ipv6-prefix | | | | | +--rw
l4-src-port? inet:port-number | | | | | +--rw target-sites* svc-id
{target-sites}? | | | | | +--rw l4-src-port-range | | | | | | +--rw
lower-port? inet:port-number | | | | | | +--rw upper-port?
inet:port-number | | | | | +--rw l4-dst-port? inet:port-number | | | |
| +--rw l4-dst-port-range | | | | | | +--rw lower-port?
inet:port-number | | | | | | +--rw upper-port? inet:port-number | | |
| | +--rw protocol-field? union | | | | +--:(match-application) | | |
| +--rw match-application? identityref | | | +--rw target-class-id?
string | | +--rw qos-profile | | +--rw (qos-profile)? | |
+--:(standard) | | | +--rw profile? ->
/l3vpn-svc/vpn-profiles/valid-provider-identifiers/qos-profile-identifier/id
| | +--:(custom) | | +--rw classes {qos-custom}? | | +--rw class*
[class-id] | | +--rw class-id string | | +--rw direction? identityref
| | +--rw rate-limit? decimal64 | | +--rw latency | | | +--rw
(flavor)? | | | +--:(lowest) | | | | +--rw use-lowest-latency? empty |
| | +--:(boundary) | | | +--rw latency-boundary? uint16 | | +--rw
jitter | | | +--rw (flavor)? | | | +--:(lowest) | | | | +--rw
use-lowest-jitter? empty | | | +--:(boundary) | | | +--rw
latency-boundary? uint32 | | +--rw bandwidth | | +--rw
guaranteed-bw-percent decimal64 | | +--rw end-to-end? empty | +--rw
carrierscarrier {carrierscarrier}? | | +--rw signalling-type?
enumeration | +--rw multicast {multicast}? | +--rw
multicast-site-type? enumeration | +--rw multicast-address-family | |
+--rw ipv4? boolean {ipv4}? | | +--rw ipv6? boolean {ipv6}? | +--rw
protocol-type? enumeration +--rw routing-protocols | +--rw
routing-protocol* [type] | +--rw type identityref | +--rw ospf
{rtg-ospf}? | | +--rw address-family* address-family | | +--rw
area-address yang:dotted-quad | | +--rw metric? uint16 | | +--rw
sham-links {rtg-ospf-sham-link}? | | +--rw sham-link* [target-site] |
| +--rw target-site svc-id | | +--rw metric? uint16 | +--rw bgp
{rtg-bgp}? | | +--rw autonomous-system uint32 | | +--rw
address-family* address-family | +--rw static | | +--rw
cascaded-lan-prefixes | | +--rw ipv4-lan-prefixes* [lan next-hop]
{ipv4}? | | | +--rw lan inet:ipv4-prefix | | | +--rw lan-tag? string |
| | +--rw next-hop inet:ipv4-address | | +--rw ipv6-lan-prefixes* [lan
next-hop] {ipv6}? | | +--rw lan inet:ipv6-prefix | | +--rw lan-tag?
string | | +--rw next-hop inet:ipv6-address | +--rw rip {rtg-rip}? | |
+--rw address-family* address-family | +--rw vrrp {rtg-vrrp}? | +--rw
address-family* address-family +--rw availability | +--rw
access-priority? uint32 +--rw vpn-attachment +--rw (attachment-flavor)
+--:(vpn-policy-id) | +--rw vpn-policy-id? ->
../../../../vpn-policies/vpn-policy/vpn-policy-id +--:(vpn-id) +--rw
vpn-id? -> /l3vpn-svc/vpn-services/vpn-service/vpn-id +--rw
site-role? identityref
The model defined in this document implements many features that allow implementations to be modular. As an example, an implementation may support only IPv4 VPNs (IPv4 feature), IPv6 VPNs (IPv6 feature), or both (by advertising both features). The routing protocols proposed to the customer may also be enabled through features. This model also defines some features for options that are more advanced, such as support for extranet VPNs (Section 6.2.4), site diversity (Section 6.6), and QoS (Section 6.12.3).
In addition, as for any YANG model, this service model can be augmented to implement new behaviors or specific features. For example, this model uses different options for IP address assignments; if those options do not fulfill all requirements, new options can be added through augmentation.
A vpn-service list item contains generic information about the VPN service. The "vpn-id" provided in the vpn-service list refers to an internal reference for this VPN service, while the customer name refers to a more-explicit reference to the customer. This identifier is purely internal to the organization responsible for the VPN service.
The type of VPN service topology is required for configuration. Our proposed model supports any-to-any, Hub and Spoke (where Hubs can exchange traffic), and "Hub and Spoke disjoint" (where Hubs cannot exchange traffic). New topologies could be added via augmentation. By default, the any-to-any VPN service topology is used.
A Layer 3 PE-based VPN is built using route targets (RTs) as described in [RFC4364]. The management system is expected to automatically allocate a set of RTs upon receiving a VPN service creation request. How the management system allocates RTs is out of scope for this document, but multiple ways could be envisaged, as described below.
Management system
<------------------------------------------------->
Request RT +-----------------------+ Topo a2a +----------+
RESTCONF | | -----> | | User ------------- | Service
Orchestration | | Network | l3vpn-svc | | <----- | OSS |
Model +-----------------------+ Response +----------+ RT1, RT2
In the example above, a service orchestration, owning the instantiation of this service model, requests RTs to the network OSS. Based on the requested VPN service topology, the network OSS replies with one or multiple RTs. The interface between this service orchestration and the network OSS is out of scope for this document.
+---------------------------+ RESTCONF
| | User ------------- | Service Orchestration | l3vpn-svc | |
Model | | | RT pool: 10:1->10:10000 | | RT pool:
20:50->20:5000 | +---------------------------+
In the example above, a service orchestration, owning the instantiation of this service model, owns one or more pools of RTs (specified by the SP) that can be allocated. Based on the requested VPN service topology, it will allocate one or multiple RTs from the pool.
The mechanisms shown above are just examples and should not be considered an exhaustive list of solutions.
+------------------------------------------------------------+ |
VPN1_Site1 ------ PE1 PE2 ------ VPN1_Site2 | | | | VPN1_Site3
------ PE3 PE4 ------ VPN1_Site4 |
+------------------------------------------------------------+
Any-to-Any VPN Service Topology
In the any-to-any VPN service topology, all VPN sites can communicate with each other without any restrictions. The management system that receives an any-to-any IP VPN service request through this model is expected to assign and then configure the VRF and RTs on the appropriate PEs. In the any-to-any case, a single RT is generally required, and every VRF imports and exports this RT.
+-------------------------------------------------------------+
| Hub_Site1 ------ PE1 PE2 ------ Spoke_Site1 | |
+----------------------------------+ | | |
+----------------------------------+ | Hub_Site2 ------ PE3 PE4
------ Spoke_Site2 |
+-------------------------------------------------------------+
Hub-and-Spoke VPN Service Topology
In the Hub-and-Spoke VPN service topology, all Spoke sites can communicate only with Hub sites but not with each other, and Hubs can also communicate with each other. The management system that owns an any-to-any IP VPN service request through this model is expected to assign and then configure the VRF and RTs on the appropriate PEs. In the Hub-and-Spoke case, two RTs are generally required (one RT for Hub routes and one RT for Spoke routes). A Hub VRF that connects Hub sites will export Hub routes with the Hub RT and will import Spoke routes through the Spoke RT. It will also import the Hub RT to allow Hub-to-Hub communication. A Spoke VRF that connects Spoke sites will export Spoke routes with the Spoke RT and will import Hub routes through the Hub RT.
The management system MUST take into account constraints on Hub-and- Spoke connections. For example, if a management system decides to mesh a Spoke site and a Hub site on the same PE, it needs to mesh connections in different VRFs, as shown in the figure below.
Hub_Site ------- (VRF_Hub) PE1
(VRF_Spoke) / | Spoke_Site1 -------------------+ | | Spoke_Site2
-----------------------+
+-------------------------------------------------------------+
| Hub_Site1 ------ PE1 PE2 ------ Spoke_Site1 |
+--------------------------+ +-------------------------------+ |
| +--------------------------+ +-------------------------------+
| Hub_Site2 ------ PE3 PE4 ------ Spoke_Site2 |
+-------------------------------------------------------------+
Hub and Spoke Disjoint VPN Service Topology
In the Hub and Spoke disjoint VPN service topology, all Spoke sites can communicate only with Hub sites but not with each other, and Hubs cannot communicate with each other. The management system that owns an any-to-any IP VPN service request through this model is expected to assign and then configure the VRF and RTs on the appropriate PEs. In the Hub-and-Spoke case, two RTs are required (one RT for Hub routes and one RT for Spoke routes). A Hub VRF that connects Hub sites will export Hub routes with the Hub RT and will import Spoke routes through the Spoke RT. A Spoke VRF that connects Spoke sites will export Spoke routes with the Spoke RT and will import Hub routes through the Hub RT.
The management system MUST take into account constraints on Hub-and- Spoke connections, as in the previous case.
Hub and Spoke disjoint can also be seen as multiple Hub-and-Spoke VPNs (one per Hub) that share a common set of Spoke sites.
The proposed model provides cloud access configuration via the "cloud-accesses" container. The usage of cloud-access is targeted for the public cloud. An Internet access can also be considered a public cloud access service. The cloud-accesses container provides parameters for network address translation and authorization rules.
A private cloud access may be addressed through NNIs, as described in Section 6.15.
A cloud identifier is used to reference the target service. This identifier is local to each administration.
The model allows for source address translation before accessing the cloud. IPv4-to-IPv4 address translation (NAT44) is the only supported option, but other options can be added through augmentation. If IP source address translation is required to access the cloud, the "enabled" leaf MUST be set to true in the "nat44" container. An IP address may be provided in the "customer-address" leaf if the customer is providing the IP address to be used for the cloud access. If the SP is providing this address, "customer-address" is not necessary, as it can be picked from a pool of SPs.
By default, all sites in the IP VPN MUST be authorized to access the cloud. If restrictions are required, a user MAY configure the "permit-site" or "deny-site" leaf-list. The permit-site leaf-list defines the list of sites authorized for cloud access. The deny-site leaf-list defines the list of sites denied for cloud access. The model supports both "deny-any-except" and "permit-any-except" authorization.
How the restrictions will be configured on network elements is out of scope for this document.
IP VPN ++++++++++++++++++++++++++++++++
++++++++++++ + Site 3 + --- + Cloud 1 + + Site 1 + ++++++++++++ +
+ + Site 2 + --- ++++++++++++ + + + Internet + + Site 4 +
++++++++++++ ++++++++++++++++++++++++++++++++ | +++++++++++ +
Cloud 2 + +++++++++++
In the example above, we configure the global VPN to access the Internet by creating a cloud-access pointing to the cloud identifier for the Internet service. No authorized sites will be configured, as all sites are required to access the Internet. The "address-translation/nat44/enabled" leaf will be set to true.
<?xml version="1.0"?> <l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-services> <vpn-service>
<vpn-id>123456487</vpn-id> <cloud-accesses>
<cloud-access>
<cloud-identifier>INTERNET</cloud-identifier>
<address-translation> <nat44>
<enabled>true</enabled> </nat44>
</address-translation> </cloud-access>
</cloud-accesses> </vpn-service> </vpn-services>
</l3vpn-svc>
If Site 1 and Site 2 require access to Cloud 1, a new cloud-access pointing to the cloud identifier of Cloud 1 will be created. The permit-site leaf-list will be filled with a reference to Site 1 and Site 2.
<?xml version="1.0"?> <l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-services> <vpn-service>
<vpn-id>123456487</vpn-id> <cloud-accesses>
<cloud-access>
<cloud-identifier>Cloud1</cloud-identifier>
<permit-site>site1</permit-site>
<permit-site>site2</permit-site> </cloud-access>
</cloud-accesses> </vpn-service> </vpn-services>
</l3vpn-svc>
If all sites except Site 1 require access to Cloud 2, a new cloud-access pointing to the cloud identifier of Cloud 2 will be created. The deny-site leaf-list will be filled with a reference to Site 1.
<?xml version="1.0"?> <l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-services> <vpn-service>
<vpn-id>123456487</vpn-id> <cloud-accesses>
<cloud-access>
<cloud-identifier>Cloud2</cloud-identifier>
<deny-site>site1</deny-site> </cloud-access>
</cloud-accesses> </vpn-service> </vpn-services>
</l3vpn-svc>
A service with more than one cloud access is functionally identical to multiple services each with a single cloud access, where the sites that belong to each service in the latter case correspond with the authorized sites for each cloud access in the former case. However, defining a single service with multiple cloud accesses may be operationally simpler.
Multicast in IP VPNs is described in [RFC6513].
If multicast support is required for an IP VPN, some global multicast parameters are required as input for the service request.
Users of this model will need to provide the flavors of trees that will be used by customers within the IP VPN (customer tree). The proposed model supports bidirectional, shared, and source-based trees (and can be augmented). Multiple flavors of trees can be supported simultaneously.
Operator network ______________ / \ | |
(SSM tree) | Recv (IGMPv3) -- Site2 ------- PE2 | | PE1 --- Site1
--- Source1 | | \ | | -- Source2 | | (ASM tree) | Recv (IGMPv2) --
Site3 ------- PE3 | | | (SSM tree) | Recv (IGMPv3) -- Site4
------- PE4 | | / | Recv (IGMPv2) -- Site5 -------- | (ASM tree) |
| | \_______________/
When an ASM flavor is requested, this model requires that the "rp" and "rp-discovery" parameters be filled. Multiple RP-to-group mappings can be created using the "rp-group-mappings" container. For each mapping, the SP can manage the RP service by setting the "provider-managed/enabled" leaf to true. In the case of a provider- managed RP, the user can request RP redundancy and/or optimal traffic delivery. Those parameters will help the SP select the appropriate technology or architecture to fulfill the customer service requirement: for instance, in the case of a request for optimal traffic delivery, an SP may use Anycast-RP or RP-tree-to-SPT switchover architectures.
In the case of a customer-managed RP, the RP address must be filled in the RP-to-group mappings using the "rp-address" leaf. This leaf is not needed for a provider-managed RP.
Users can define a specific mechanism for RP discovery, such as the "auto-rp", "static-rp", or "bsr-rp" modes. By default, the model uses "static-rp" if ASM is requested. A single rp-discovery mechanism is allowed for the VPN. The "rp-discovery" container can be used for both provider-managed and customer-managed RPs. In the case of a provider-managed RP, if the user wants to use "bsr-rp" as a discovery protocol, an SP should consider the provider-managed "rp-group-mappings" for the "bsr-rp" configuration. The SP will then configure its selected RPs to be "bsr-rp-candidates". In the case of a customer-managed RP and a "bsr-rp" discovery mechanism, the "rp-address" provided will be the bsr-rp candidate.
There are some cases where a particular VPN needs access to resources (servers, hosts, etc.) that are external. Those resources may be located in another VPN.
+-----------+ +-----------+ / \ / \ Site
A -- | VPN A | --- | VPN B | --- Site B \ / \ / (Shared
+-----------+ +-----------+ resources)
In the figure above, VPN B has some resources on Site B that need to be available to some customers/partners. VPN A must be able to access those VPN B resources.
Such a VPN connection scenario can be achieved via a VPN policy as defined in Section 6.5.2.2. But there are some simple cases where a particular VPN (VPN A) needs access to all resources in another VPN (VPN B). The model provides an easy way to set up this connection using the "extranet-vpns" container.
The extranet-vpns container defines a list of VPNs a particular VPN wants to access. The extranet-vpns container must be used on customer VPNs accessing extranet resources in another VPN. In the figure above, in order to provide VPN A with access to VPN B, the extranet-vpns container needs to be configured under VPN A with an entry corresponding to VPN B. There is no service configuration requirement on VPN B.
Readers should note that even if there is no configuration requirement on VPN B, if VPN A lists VPN B as an extranet, all sites in VPN B will gain access to all sites in VPN A.
The "site-role" leaf defines the role of the local VPN sites in the target extranet VPN service topology. Site roles are defined in Section 6.4. Based on this, the requirements described in Section 6.4 regarding the site-role leaf are also applicable here.
In the example below, VPN A accesses VPN B resources through an extranet connection. A Spoke role is required for VPN A sites, as sites from VPN A must not be able to communicate with each other through the extranet VPN connection.
<?xml version="1.0"?> <l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-services> <vpn-service>
<vpn-id>VPNB</vpn-id>
<vpn-service-topology>hub-spoke</vpn-service-topology>
</vpn-service> <vpn-service>
<vpn-id>VPNA</vpn-id>
<vpn-service-topology>any-to-any</vpn-service-topology>
<extranet-vpns> <extranet-vpn>
<vpn-id>VPNB</vpn-id>
<local-sites-role>spoke-role</local-sites-role>
</extranet-vpn> </extranet-vpns> </vpn-service>
</vpn-services> </l3vpn-svc>
This model does not define how the extranet configuration will be achieved.
Any VPN interconnection scenario that is more complex (e.g., only certain parts of sites on VPN A accessing only certain parts of sites on VPN B) needs to be achieved using a VPN attachment as defined in Section 6.5.2, and especially a VPN policy as defined in Section 6.5.2.2.
A site represents a connection of a customer office to one or more VPN services. Each site is associated with one or more location.
+-------------+ / \ +------------------+
+-----| VPN1 | | | | \ / | New York Office |------ (site) -----+
+-------------+ | | | +-------------+ +------------------+ | / \
+-----| VPN2 | \ / +-------------+
A site has several characteristics:
A site-network-access represents an IP logical connection of a site. A site may have multiple site-network-accesses.
+------------------+ Site |
|----------------------------------- | |******
(site-network-access#1) ****** | New York Office | | |******
(site-network-access#2) ****** |
|----------------------------------- +------------------+
Multiple site-network-accesses are used, for instance, in the case of multihoming. Some other meshing cases may also include multiple site-network-accesses.
The site configuration is viewed as a global entity; we assume that it is mostly the management system's role to split the parameters between the different elements within the network. For example, in the case of the site-network-access configuration, the management system needs to split the overall parameters between the PE configuration and the CE configuration.
A site may be composed of multiple locations. All the locations will need to be configured as part of the "locations" container and list. A typical example of a multi-location site is a headquarters office in a city composed of multiple buildings. Those buildings may be located in different parts of the city and may be linked by intra-city fibers (customer metropolitan area network). In such a case, when connecting to a VPN service, the customer may ask for multihoming based on its distributed locations.
New York Site +------------------+ Site |
+--------------+ |----------------------------------- | |
Manhattan | |****** (site-network-access#1) ****** |
+--------------+ | | +--------------+ | | | Brooklyn | |******
(site-network-access#2) ****** | +--------------+ | |
|----------------------------------- +------------------+
A customer may also request some premises equipment entities (CEs) from the SP via the "devices" container. Requesting a CE implies a provider-managed or co-managed model. A particular device must be ordered to a particular already-configured location. This would help the SP send the device to the appropriate postal address. In a multi-location site, a customer may, for example, request a CE for each location on the site where multihoming must be implemented. In the figure above, one device may be requested for the Manhattan location and one other for the Brooklyn location.
By using devices and locations, the user can influence the multihoming scenario he wants to implement: single CE, dual CE, etc.
As mentioned earlier, a site may be multihomed. Each IP network access for a site is defined in the "site-network-accesses" container. The site-network-access parameter defines how the site is connected on the network and is split into three main classes of parameters:
The site-network-access has a specific type (site-network-access-type). This document defines two types:
The type of site-network-access may have an impact on the parameters offered to the customer, e.g., an SP may not offer encryption for multipoint accesses. It is up to the provider to decide what parameter is supported for point-to-point and/or multipoint accesses; this topic is out of scope for this document. Some containers proposed in the model may require extensions in order to work properly for multipoint accesses.
The bearer container defines the requirements for the site attachment to the provider network that are below Layer 3.
The bearer parameters will help determine the access media to be used. This is further described in Section 6.6.3.
The "ip-connection" container defines the protocol parameters of the attachment (IPv4 and IPv6). Depending on the management mode, it refers to PE-CE addressing or CE-to-customer-LAN addressing. In any case, it describes the responsibility boundary between the provider and the customer. For a customer-managed site, it refers to the PE-CE connection. For a provider-managed site, it refers to the CE-to-LAN connection.
An IP subnet can be configured for either IPv4 or IPv6 Layer 3 protocols. For a dual-stack connection, two subnets will be provided, one for each address family.
The "address-allocation-type" determines how the address allocation needs to be done. The current model defines five ways to perform IP address allocation:
In the dynamic addressing mechanism, the SP is expected to provide at least the IP address, prefix length, and default gateway information.In the case of multiple site-network-access points belonging to the same VPN, address space allocated for one site-network-access should not conflict with one allocated for other site-network-accesses.
A customer may require a specific IP connectivity fault detection mechanism on the IP connection. The model supports BFD as a fault detection mechanism. This can be extended with other mechanisms via augmentation. The provider can propose some profiles to the customer, depending on the service level the customer wants to achieve. Profile names must be communicated to the customer. This communication is out of scope for this document. Some fixed values for the holdtime period may also be imposed by the customer if the provider allows the customer this function.
The "oam" container can easily be augmented by other mechanisms; in particular, work done by the LIME Working Group (https://datatracker.ietf.org/wg/lime/charter/) may be reused in applicable scenarios.
Some parameters can be configured at both the site level and the site-network-access level, e.g., routing, services, security. Inheritance applies when parameters are defined at the site level. If a parameter is configured at both the site level and the access level, the access-level parameter MUST override the site-level parameter. Those parameters will be described later in this document.
In terms of provisioning impact, it will be up to the implementation to decide on the appropriate behavior when modifying existing configurations. But the SP will need to communicate to the user about the impact of using inheritance. For example, if we consider that a site has already provisioned three site-network-accesses, what will happen if a customer changes a service parameter at the site level? An implementation of this model may update the service parameters of all already-provisioned site-network-accesses (with potential impact on live traffic), or it may take into account this new parameter only for the new sites.
A VPN has a particular service topology, as described in Section 6.2.1. As a consequence, each site belonging to a VPN is assigned with a particular role in this topology. The site-role leaf defines the role of the site in a particular VPN topology.
In the any-to-any VPN service topology, all sites MUST have the same role, which will be "any-to-any-role".
In the Hub-and-Spoke VPN service topology or the Hub and Spoke disjoint VPN service topology, sites MUST have a Hub role or a Spoke role.
A site may be part of one or multiple VPNs. The "site-vpn-flavor" defines the way the VPN multiplexing is done. The current version of the model supports four flavors:
The figure below describes a single VPN attachment. The site connects to only one VPN.
+--------+ +------------------+ Site /
\ | |-----------------------------| | |
|***(site-network-access#1)***| VPN1 | | New York Office | | | |
|***(site-network-access#2)***| | |
|-----------------------------| | +------------------+ \ /
+--------+
The figure below describes a site connected to multiple VPNs.
+---------+ +---/----+ \
+------------------+ Site / | \ | |
|--------------------------------- | |VPN B| |
|***(site-network-access#1)******* | | | | New York Office | | |
| | | |***(site-network-access#2)******* \ | / |
|-----------------------------| VPN A+-----|---+
+------------------+ \ / +--------+
In the example above, the New York office is multihomed. Both logical accesses are using the same VPN attachment rules, and both are connected to VPN A and VPN B.
Reaching VPN A or VPN B from the New York office will be done via destination-based routing. Having the same destination reachable from the two VPNs may cause routing troubles. The customer administration's role in this case would be to ensure the appropriate mapping of its prefixes in each VPN.
The figure below describes a subVPN attachment. The site connects to multiple VPNs, but each logical access is attached to a particular set of VPNs. A typical use case for a subVPN is a customer site used by multiple affiliates with private resources for each affiliate that cannot be shared (communication between the affiliates is prevented). It is similar to have separate sites, but in the case of a SubVPN, the customer can share some physical components at a single location, while maintaining strong communication isolation between the affiliates. In this example, site-network-access#1 is attached to VPN B, while site-network-access#2 is attached to VPN A.
+------------------+ Site +--------+ |
|----------------------------------/ \ |
|****(site-network-access#1)******| VPN B | | New York Office |
\ / | | +--------+ | | +--------+ | | / \ |
|****(site-network-access#2)******| VPN A | | | \ / | |
+--------+ | |-----------------------------------
+------------------+
A multiVPN can be implemented in addition to a subVPN; as a consequence, each site-network-access can access multiple VPNs. In the example below, site-network-access#1 is mapped to VPN B and VPN C, while site-network-access#2 is mapped to VPN A and VPN D.
+-----------------+ Site +------+ |
|--------------------------------/ +-----+ |
|****(site-network-access#1)****| VPN B / \ | New York Office |
\ | VPN C | | | +-----\ / | | +-----+ | | | | +-------+ | | /
+-----+ | |****(site-network-access#2)****| VPN A / \ | | \ |
VPN D | | | +------\ / | |---------------------------------
+-----+ +-----------------+
Multihoming is also possible with subVPNs; in this case, site-network-accesses are grouped, and a particular group will have access to the same set of VPNs. In the example below, site-network-access#1 and site-network-access#2 are part of the same group (multihomed together) and are mapped to VPN B and VPN C; in addition, site-network-access#3 and site-network-access#4 are part of the same group (multihomed together) and are mapped to VPN A and VPN D.
+-----------------+ Site +------+ |
|---------------------------------/ +-----+ |
|****(site-network-access#1)*****| VPN B / \ | New York Office
|****(site-network-access#2)***** \ | VPN C | | | +-----\ / | |
+-----+ | | | | +------+ | | / +-----+ |
|****(site-network-access#3)*****| VPN A / \ |
|****(site-network-access#4)***** \ | VPN D | | | +-----\ / |
|---------------------------------- +-----+ +-----------------+
In terms of service configuration, a subVPN can be achieved by requesting that the site-network-access use the same bearer (see Section 6.6.4 for more details).
A Network-to-Network Interface (NNI) scenario may be modeled using the sites container (see Section 6.15.1). Using the sites container to model an NNI is only one possible option for NNIs (see Section 6.15). This option is called "option A" by reference to the option A NNI defined in [RFC4364]. It is helpful for the SP to indicate that the requested VPN connection is not a regular site but rather is an NNI, as specific default device configuration parameters may be applied in the case of NNIs (e.g., ACLs, routing policies).
SP A SP B -------------------
------------------- / \ / \ | | | | | ++++++++ Inter-AS link
++++++++ | | + +_______________+ + | | +
(VRF1)---(VPN1)----(VRF1) + | | + ASBR + + ASBR + | | +
(VRF2)---(VPN2)----(VRF2) + | | + +_______________+ + | |
++++++++ ++++++++ | | | | | | | | | | | | | | ++++++++ Inter-AS
link ++++++++ | | + +_______________+ + | | +
(VRF1)---(VPN1)----(VRF1) + | | + ASBR + + ASBR + | | +
(VRF2)---(VPN2)----(VRF2) + | | + +_______________+ + | |
++++++++ ++++++++ | | | | | | | | | \ / \ / -------------------
-------------------
The figure above describes an option A NNI scenario that can be modeled using the sites container. In order to connect its customer VPNs (VPN1 and VPN2) in SP B, SP A may request the creation of some site-network-accesses to SP B. The site-vpn-flavor-nni will be used to inform SP B that this is an NNI and not a regular customer site. The site-vpn-flavor-nni may be multihomed and multiVPN as well.
Due to the multiple site-vpn flavors, the attachment of a site to an IP VPN is done at the site-network-access (logical access) level through the "vpn-attachment" container. The vpn-attachment container is mandatory. The model provides two ways to attach a site to a VPN:
A choice is implemented to allow the user to choose the flavor that provides the best fit.
Referencing a vpn-id provides an easy way to attach a particular logical access to a VPN. This is the best way in the case of a single VPN attachment or subVPN with a single VPN attachment per logical access. When referencing a vpn-id, the site-role setting must be added to express the role of the site in the target VPN service topology.
<?xml version="1.0"?>
<l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-services> <vpn-service>
<vpn-id>VPNA</vpn-id> </vpn-service>
<vpn-service> <vpn-id>VPNB</vpn-id>
</vpn-service> </vpn-services> <sites>
<site> <site-id>SITE1</site-id>
<locations> <location>
<location-id>L1</location-id> </location>
</locations> <management>
<type>customer-managed</type> </management>
<security> <encryption>
<layer>layer3</layer> </encryption>
</security> <site-network-accesses>
<site-network-access>
<site-network-access-id>LA1</site-network-access-id>
<ip-connection> <ipv4>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv4> <ipv6>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv6> </ip-connection> <service>
<svc-mtu>1514</svc-mtu>
<svc-input-bandwidth>10000000</svc-input-bandwidth>
<svc-output-bandwidth>10000000</svc-output-bandwidth>
</service> <security> <encryption>
<layer>layer3</layer> </encryption>
</security>
<location-reference>L1</location-reference>
<vpn-attachment> <vpn-id>VPNA</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
<site-network-access>
<site-network-access-id>LA2</site-network-access-id>
<ip-connection> <ipv4>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv4> <ipv6>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv6> </ip-connection> <service>
<svc-mtu>1514</svc-mtu>
<svc-input-bandwidth>10000000</svc-input-bandwidth>
<svc-output-bandwidth>10000000</svc-output-bandwidth>
</service> <security> <encryption>
<layer>layer3</layer> </encryption>
</security>
<location-reference>L1</location-reference>
<vpn-attachment> <vpn-id>VPNB</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
</site-network-accesses> </site> </sites>
</l3vpn-svc>
The example of a corresponding XML snippet above describes a subVPN case where a site (SITE1) has two logical accesses (LA1 and LA2), with LA1 attached to VPNA and LA2 attached to VPNB.
The "vpn-policy" list helps express a multiVPN scenario where a logical access belongs to multiple VPNs. Multiple VPN policies can be created to handle the subVPN case where each logical access is part of a different set of VPNs.
As a site can belong to multiple VPNs, the vpn-policy list may be composed of multiple entries. A filter can be applied to specify that only some LANs of the site should be part of a particular VPN. Each time a site (or LAN) is attached to a VPN, the user must precisely describe its role (site-role) within the target VPN service topology.
+--------------------------------------------------------------+
| Site1 ------ PE7 | +-------------------------+ (VPN2) | | |
+-------------------------+ | | Site2 ------ PE3 PE4 ------
Site3 | +----------------------------------+ | | |
+------------------------------------------------------------+ |
| Site4 ------ PE5 | PE6 ------ Site5 | | | | | | (VPN3) | |
+------------------------------------------------------------+ |
| | +---------------------------+
In the example above, Site5 is part of two VPNs: VPN3 and VPN2. It will play a Hub role in VPN2 and an any-to-any role in VPN3. We can express such a multiVPN scenario with the following XML snippet:
<?xml version="1.0"?>
<l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-services> <vpn-service>
<vpn-id>VPN2</vpn-id> </vpn-service>
<vpn-service> <vpn-id>VPN3</vpn-id>
</vpn-service> </vpn-services> <sites>
<site> <site-id>Site5</site-id>
<devices> <device>
<device-id>D1</device-id> </device>
</devices> <management>
<type>provider-managed</type> </management>
<security> <encryption>
<layer>layer3</layer> </encryption>
</security> <vpn-policies> <vpn-policy>
<vpn-policy-id>POLICY1</vpn-policy-id>
<entries> <id>ENTRY1</id> <vpn>
<vpn-id>VPN2</vpn-id>
<site-role>hub-role</site-role> </vpn>
</entries> <entries> <id>ENTRY2</id>
<vpn> <vpn-id>VPN3</vpn-id>
<site-role>any-to-any-role</site-role> </vpn>
</entries> </vpn-policy> </vpn-policies>
<site-network-accesses> <site-network-access>
<site-network-access-id>LA1</site-network-access-id>
<device-reference>D1</device-reference>
<ip-connection> <ipv4>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv4> <ipv6>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv6> </ip-connection> <service>
<svc-mtu>1514</svc-mtu>
<svc-input-bandwidth>10000000</svc-input-bandwidth>
<svc-output-bandwidth>10000000</svc-output-bandwidth>
</service> <security> <encryption>
<layer>layer3</layer> </encryption>
</security> <vpn-attachment>
<vpn-policy-id>POLICY1</vpn-policy-id>
</vpn-attachment> </site-network-access>
</site-network-accesses> </site> </sites>
</l3vpn-svc>
Now, if a more-granular VPN attachment is necessary, filtering can be used. For example, if LAN1 from Site5 must be attached to VPN2 as a Hub and LAN2 must be attached to VPN3, the following configuration of corresponding XML snippet can be used:
<?xml version="1.0"?>
<l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-services> <vpn-service>
<vpn-id>VPN2</vpn-id> </vpn-service>
<vpn-service> <vpn-id>VPN3</vpn-id>
</vpn-service> </vpn-services> <sites>
<site> <site-id>Site5</site-id>
<vpn-policies> <vpn-policy>
<vpn-policy-id>POLICY1</vpn-policy-id>
<entries> <id>ENTRY1</id> <filters>
<filter> <type>lan</type>
<lan-tag>LAN1</lan-tag> </filter>
</filters> <vpn> <vpn-id>VPN2</vpn-id>
<site-role>hub-role</site-role> </vpn>
</entries> <entries> <id>ENTRY2</id>
<filters> <filter> <type>lan</type>
<lan-tag>LAN2</lan-tag> </filter>
</filters> <vpn> <vpn-id>VPN3</vpn-id>
<site-role>any-to-any-role</site-role> </vpn>
</entries> </vpn-policy> </vpn-policies>
<site-network-accesses> <site-network-access>
<site-network-access-id>LA1</site-network-access-id>
<vpn-attachment>
<vpn-policy-id>POLICY1</vpn-policy-id>
</vpn-attachment> </site-network-access>
</site-network-accesses> </site> </sites>
</l3vpn-svc>
The management system will have to determine where to connect each site-network-access of a particular site to the provider network (e.g., PE, aggregation switch).
The current model defines parameters and constraints that can influence the meshing of the site-network-access.
The management system MUST honor all customer constraints, or if a constraint is too strict and cannot be fulfilled, the management system MUST NOT provision the site and MUST provide information to the user about which constraints that could not be fulfilled.How the information is provided is out of scope for this document. Whether or not to relax the constraint would then be left up to the user.
Parameters such as site location (see Section 6.6.2) and access type are just hints (see Section 6.6.3) for the management system for service placement.
In addition to parameters and constraints, the management system's decision MAY be based on any other internal constraints that are left up to the SP: least load, distance, etc.
In the case of provider management or co-management, one or more devices have been ordered by the customer to a particular already-configured location. The customer may force a particular site-network-access to be connected on a particular device that he ordered.
New York Site +------------------+ Site |
+--------------+ |----------------------------------- | |
Manhattan | | | | CE1********* (site-network-access#1) ****** |
+--------------+ | | +--------------+ | | | Brooklyn CE2*********
(site-network-access#2) ****** | +--------------+ | |
|----------------------------------- +------------------+
In the figure above, site-network-access#1 is associated with CE1 in the service request. The SP must ensure the provisioning of this connection.
The location information provided in this model MAY be used by a management system to determine the target PE to mesh the site (SP side). A particular location must be associated with each site network access when configuring it. The SP MUST honor the termination of the access on the location associated with the site network access (customer side). The "country-code" in the site location SHOULD be expressed as an ISO ALPHA-2 code.
The site-network-access location is determined by the "location-flavor". In the case of a provider-managed or co-managed site, the user is expected to configure a "device-reference" (device case) that will bind the site-network-access to a particular device that the customer ordered. As each device is already associated with a particular location, in such a case the location information is retrieved from the device location. In the case of a customer- managed site, the user is expected to configure a "location-reference" (location case); this provides a reference to an existing configured location and will help with placement.
POP#1 (New York) +---------+ | PE1 | Site
#1 ---... | PE2 | (Atlantic City) | PE3 | +---------+ POP#2
(Washington) +---------+ | PE4 | | PE5 | | PE6 | +---------+ POP#3
(Philadelphia) +---------+ | PE7 | Site #2 CE#1---... | PE8 |
(Reston) | PE9 | +---------+
In the example above, Site #1 is a customer-managed site with a location L1, while Site #2 is a provider-managed site for which a CE (CE#1) was ordered. Site #2 is configured with L2 as its location. When configuring a site-network-access for Site #1, the user will need to reference location L1 so that the management system will know that the access will need to terminate on this location. Then, for distance reasons, this management system may mesh Site #1 on a PE in the Philadelphia POP. It may also take into account resources available on PEs to determine the exact target PE (e.g., least loaded). For Site #2, the user is expected to configure the site-network-access with a device-reference to CE#1 so that the management system will know that the access must terminate on the location of CE#1 and must be connected to CE#1. For placement of the SP side of the access connection, in the case of the nearest PE used, it may mesh Site #2 on the Washington POP.
The management system needs to elect the access media to connect the site to the customer (for example, xDSL, leased line, Ethernet backhaul). The customer may provide some parameters/constraints that will provide hints to the management system.
The bearer container information SHOULD be the first piece of information considered when making this decision:
Any other internal parameters from the SP can also be used. The management system MAY use other parameters, such as the requested "svc-input-bandwidth" and "svc-output-bandwidth", to help decide which access type to use.
Each site-network-access may have one or more constraints that would drive the placement of the access. By default, the model assumes that there are no constraints, but allocation of a unique bearer per site-network-access is expected.
In order to help with the different placement scenarios, a site-network-access may be tagged using one or multiple group identifiers. The group identifier is a string, so it can accommodate both explicit naming of a group of sites (e.g., "multihomed-set1" or "subVPN") and the use of a numbered identifier (e.g., 12345678). The meaning of each group-id is local to each customer administrator, and the management system MUST ensure that different customers can use the same group-ids. One or more group-ids can also be defined at the site level; as a consequence, all site-network-accesses under the site MUST inherit the group-ids of the site they belong to. When, in addition to the site group-ids some group-ids are defined at the site-network-access level, the management system MUST consider the union of all groups (site level and site network access level) for this particular site-network-access.
For an already-configured site-network-access, each constraint MUST be expressed against a targeted set of site-network-accesses. This site-network-access MUST never be taken into account in the targeted set -- for example, "My site-network-access S must not be connected on the same POP as the site-network-accesses that are part of Group 10." The set of site-network-accesses against which the constraint is evaluated can be expressed as a list of groups, "all-other-accesses", or "all-other-groups". The all-other-accesses option means that the current site-network-access constraint MUST be evaluated against all the other site-network-accesses belonging to the current site. The all-other-groups option means that the constraint MUST be evaluated against all groups that the current site-network-access does not belong to.
The current model defines multiple constraint-types:
These constraint-types can be extended through augmentation.
Each constraint is expressed as "The site-network-access S must be <constraint-type> (e.g., pe-diverse, pop-diverse) from these <target> site-network-accesses."
The group-id used to target some site-network-accesses may be the same as the one used by the current site-network-access. This eases the configuration of scenarios where a group of site-network-access points has a constraint between the access points in the group. As an example, if we want a set of sites (Site#1 to Site#5) to be connected on different PEs, we can tag them with the same group-id and express a pe-diverse constraint for this group-id with the following XML snippet:
<?xml version="1.0"?> <l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-services> <vpn-service>
<vpn-id>VPNA</vpn-id> </vpn-service>
</vpn-services> <sites> <site>
<site-id>SITE1</site-id> <locations>
<location> <location-id>L1</location-id>
</location> </locations> <management>
<type>customer-managed</type> </management>
<site-network-accesses> <site-network-access>
<site-network-access-id>1</site-network-access-id>
<ip-connection> <ipv4>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv4> <ipv6>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv6> </ip-connection> <service>
<svc-mtu>1514</svc-mtu>
<svc-input-bandwidth>10000000</svc-input-bandwidth>
<svc-output-bandwidth>10000000</svc-output-bandwidth>
</service> <security> <encryption>
<layer>layer3</layer> </encryption>
</security>
<location-reference>L1</location-reference>
<access-diversity> <groups> <group>
<group-id>10</group-id> </group> </groups>
<constraints> <constraint>
<constraint-type>pe-diverse</constraint-type>
<target> <group> <group-id>10</group-id>
</group> </target> </constraint>
</constraints> </access-diversity>
<vpn-attachment> <vpn-id>VPNA</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
</site-network-accesses> </site> <site>
<site-id>SITE2</site-id> <locations>
<location> <location-id>L1</location-id>
</location> </locations> <management>
<type>customer-managed</type> </management>
<security> <encryption>
<layer>layer3</layer> </encryption>
</security> <site-network-accesses>
<site-network-access>
<site-network-access-id>1</site-network-access-id>
<ip-connection> <ipv4>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv4> <ipv6>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv6> </ip-connection> <service>
<svc-mtu>1514</svc-mtu>
<svc-input-bandwidth>10000000</svc-input-bandwidth>
<svc-output-bandwidth>10000000</svc-output-bandwidth>
</service> <security> <encryption>
<layer>layer3</layer> </encryption>
</security>
<location-reference>L1</location-reference>
<access-diversity> <groups> <group>
<group-id>10</group-id> </group> </groups>
<constraints> <constraint>
<constraint-type>pe-diverse</constraint-type>
<target> <group> <group-id>10</group-id>
</group> </target> </constraint>
</constraints> </access-diversity>
<vpn-attachment> <vpn-id>VPNA</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
</site-network-accesses> </site> ... <site>
<site-id>SITE5</site-id> <locations>
<location> <location-id>L1</location-id>
</location> </locations> <management>
<type>customer-managed</type> </management>
<security> <encryption>
<layer>layer3</layer> </encryption>
</security> <site-network-accesses>
<site-network-access>
<site-network-access-id>1</site-network-access-id>
<ip-connection> <ipv4>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv4> <ipv6>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv6> </ip-connection> <service>
<svc-mtu>1514</svc-mtu>
<svc-input-bandwidth>10000000</svc-input-bandwidth>
<svc-output-bandwidth>10000000</svc-output-bandwidth>
</service> <security> <encryption>
<layer>layer3</layer> </encryption>
</security>
<location-reference>L1</location-reference>
<access-diversity> <groups> <group>
<group-id>10</group-id> </group> </groups>
<constraints> <constraint>
<constraint-type>pe-diverse</constraint-type>
<target> <group> <group-id>10</group-id>
</group> </target> </constraint>
</constraints> </access-diversity>
<vpn-attachment> <vpn-id>VPNA</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
</site-network-accesses> </site> </sites>
</l3vpn-svc>
The group-id used to target some site-network-accesses may also be different than the one used by the current site-network-access. This can be used to express that a group of sites has some constraints against another group of sites, but there is no constraint within the group. For example, we consider a set of six sites and two groups; we want to ensure that a site in the first group must be pop-diverse from a site in the second group. The example of a corresponding XML snippet is described as follows:
<?xml version="1.0"?> <l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-services> <vpn-service>
<vpn-id>VPNA</vpn-id> </vpn-service>
</vpn-services> <sites> <site>
<site-id>SITE1</site-id> <site-network-accesses>
<site-network-access>
<site-network-access-id>1</site-network-access-id>
<access-diversity> <groups> <group>
<group-id>10</group-id> </group> </groups>
<constraints> <constraint>
<constraint-type>pop-diverse</constraint-type>
<target> <group> <group-id>20</group-id>
</group> </target> </constraint>
</constraints> </access-diversity>
<vpn-attachment> <vpn-id>VPNA</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
</site-network-accesses> </site> <site>
<site-id>SITE2</site-id> <site-network-accesses>
<site-network-access>
<site-network-access-id>1</site-network-access-id>
<access-diversity> <groups> <group>
<group-id>10</group-id> </group> </groups>
<constraints> <constraint>
<constraint-type>pop-diverse</constraint-type>
<target> <group> <group-id>20</group-id>
</group> </target> </constraint>
</constraints> </access-diversity>
<vpn-attachment> <vpn-id>VPNA</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
</site-network-accesses> </site> ... <site>
<site-id>SITE5</site-id> <site-network-accesses>
<site-network-access>
<site-network-access-id>1</site-network-access-id>
<access-diversity> <groups> <group>
<group-id>20</group-id> </group> </groups>
<constraints> <constraint>
<constraint-type>pop-diverse</constraint-type>
<target> <group> <group-id>10</group-id>
</group> </target> </constraint>
</constraints> </access-diversity>
<vpn-attachment> <vpn-id>VPNA</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
</site-network-accesses> </site> <site>
<site-id>SITE6</site-id> <locations>
<location> <location-id>L1</location-id>
</location> </locations> <management>
<type>customer-managed</type> </management>
<security> <encryption>
<layer>layer3</layer> </encryption>
</security> <site-network-accesses>
<site-network-access>
<site-network-access-id>1</site-network-access-id>
<ip-connection> <ipv4>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv4> <ipv6>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv6> </ip-connection> <service>
<svc-mtu>1514</svc-mtu>
<svc-input-bandwidth>10000000</svc-input-bandwidth>
<svc-output-bandwidth>10000000</svc-output-bandwidth>
</service> <security> <encryption>
<layer>layer3</layer> </encryption>
</security>
<location-reference>L1</location-reference>
<access-diversity> <groups> <group>
<group-id>20</group-id> </group> </groups>
<constraints> <constraint>
<constraint-type>pop-diverse</constraint-type>
<target> <group> <group-id>10</group-id>
</group> </target> </constraint>
</constraints> </access-diversity>
<vpn-attachment> <vpn-id>VPNA</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
</site-network-accesses> </site> </sites>
</l3vpn-svc>
Some infeasible access placement scenarios could be created via the proposed configuration framework. Such infeasible access placement scenarios could result from constraints that are too restrictive, leading to infeasible access placement in the network or conflicting constraints that would also lead to infeasible access placement. An example of conflicting rules would be to request that site-network-access#1 be pe-diverse from site-network-access#2 and to request at the same time that site-network-access#2 be on the same PE as site-network-access#1. When the management system cannot determine the placement of a site-network-access, it MUST return an error message indicating that placement was not possible.
The customer wants to create a multihomed site. The site will be composed of two site-network-accesses; for resiliency purposes, the customer wants the two site-network-accesses to be meshed on different POPs.
POP#1 +-------+ +---------+ | | | PE1 |
| |---site-network-access#1----| PE2 | | | | PE3 | | |
+---------+ | Site#1| | | POP#2 | | +---------+ | | | PE4 | |
|---site-network-access#2----| PE5 | | | | PE6 | | | +---------+
+-------+
This scenario can be expressed with the following XML snippet:
<?xml version="1.0"?>
<l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-services> <vpn-service>
<vpn-id>VPNA</vpn-id> </vpn-service>
</vpn-services> <sites> <site>
<site-id>SITE1</site-id> <locations>
<location> <location-id>L1</location-id>
</location> </locations> <management>
<type>customer-managed</type> </management>
<security> <encryption>
<layer>layer3</layer> </encryption>
</security> <site-network-accesses>
<site-network-access>
<site-network-access-id>1</site-network-access-id>
<ip-connection> <ipv4>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv4> <ipv6>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv6> </ip-connection> <service>
<svc-mtu>1514</svc-mtu>
<svc-input-bandwidth>10000000</svc-input-bandwidth>
<svc-output-bandwidth>10000000</svc-output-bandwidth>
</service> <security> <encryption>
<layer>layer3</layer> </encryption>
</security>
<location-reference>L1</location-reference>
<access-diversity> <groups> <group>
<group-id>10</group-id> </group>
</groups> <constraints> <constraint>
<constraint-type>pop-diverse</constraint-type>
<target> <group> <group-id>20</group-id>
</group> </target> </constraint>
</constraints> </access-diversity>
<vpn-attachment> <vpn-id>VPNA</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
<site-network-access>
<site-network-access-id>2</site-network-access-id>
<ip-connection> <ipv4>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv4> <ipv6>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv6> </ip-connection> <service>
<svc-mtu>1514</svc-mtu>
<svc-input-bandwidth>10000000</svc-input-bandwidth>
<svc-output-bandwidth>10000000</svc-output-bandwidth>
</service> <security> <encryption>
<layer>layer3</layer> </encryption>
</security>
<location-reference>L1</location-reference>
<access-diversity> <groups> <group>
<group-id>20</group-id> </group>
</groups> <constraints> <constraint>
<constraint-type>pop-diverse</constraint-type>
<target> <group> <group-id>10</group-id>
</group> </target> </constraint>
</constraints> </access-diversity>
<vpn-attachment> <vpn-id>VPNA</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
</site-network-accesses> </site> </sites>
</l3vpn-svc>
But it can also be expressed with the following XML snippet:
<?xml version="1.0"?>
<l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-services> <vpn-service>
<vpn-id>VPNA</vpn-id> </vpn-service>
</vpn-services> <sites> <site>
<site-id>SITE1</site-id>
<site-network-accesses> <site-network-access>
<site-network-access-id>1</site-network-access-id>
<access-diversity> <constraints> <constraint>
<constraint-type>pop-diverse</constraint-type>
<target> <all-other-accesses/> </target>
</constraint> </constraints>
</access-diversity> <vpn-attachment>
<vpn-id>VPNA</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
<site-network-access>
<site-network-access-id>2</site-network-access-id>
<access-diversity> <constraints> <constraint>
<constraint-type>pop-diverse</constraint-type>
<target> <all-other-accesses/> </target>
</constraint> </constraints>
</access-diversity> <vpn-attachment>
<vpn-id>VPNA</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
</site-network-accesses> </site> </sites>
</l3vpn-svc>
The customer has six branch offices in a particular region, and he wants to prevent having all branch offices connected on the same PE.
He wants to express that three branch offices cannot be connected on the same linecard. Also, the other branch offices must be connected on a different POP. Those other branch offices cannot also be connected on the same linecard.
POP#1 +---------+ | PE1 | Office#1
---... | PE2 | Office#2 ---... | PE3 | Office#3 ---... | PE4 |
+---------+ POP#2 +---------+ Office#4 ---... | PE5 | Office#5
---... | PE6 | Office#6 ---... | PE7 | +---------+
This scenario can be expressed as follows:
<?xml version="1.0"?>
<l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-services> <vpn-service>
<vpn-id>VPNA</vpn-id> </vpn-service>
</vpn-services> <sites> <site>
<site-id>Office1</site-id> <locations>
<location> <location-id>L1</location-id>
</location> </locations> <management>
<type>customer-managed</type> </management>
<security> <encryption>
<layer>layer3</layer> </encryption>
</security> <site-network-accesses>
<site-network-access>
<site-network-access-id>1</site-network-access-id>
<ip-connection> <ipv4>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv4> <ipv6>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv6> </ip-connection> <service>
<svc-mtu>1514</svc-mtu>
<svc-input-bandwidth>10000000</svc-input-bandwidth>
<svc-output-bandwidth>10000000</svc-output-bandwidth>
</service> <security> <encryption>
<layer>layer3</layer> </encryption>
</security>
<location-reference>L1</location-reference>
<access-diversity> <groups> <group>
<group-id>10</group-id> </group>
</groups> <constraints> <constraint>
<constraint-type>pop-diverse</constraint-type>
<target> <group> <group-id>20</group-id>
</group> </target> </constraint>
<constraint>
<constraint-type>linecard-diverse</constraint-type>
<target> <group> <group-id>10</group-id>
</group> </target> </constraint>
</constraints> </access-diversity>
<vpn-attachment> <vpn-id>VPNA</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
</site-network-accesses> </site> <site>
<site-id>Office2</site-id> <locations>
<location> <location-id>L1</location-id>
</location> </locations> <management>
<type>customer-managed</type> </management>
<security> <encryption>
<layer>layer3</layer> </encryption>
</security> <site-network-accesses>
<site-network-access>
<site-network-access-id>1</site-network-access-id>
<ip-connection> <ipv4>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv4> <ipv6>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv6> </ip-connection> <service>
<svc-mtu>1514</svc-mtu>
<svc-input-bandwidth>10000000</svc-input-bandwidth>
<svc-output-bandwidth>10000000</svc-output-bandwidth>
</service> <security> <encryption>
<layer>layer3</layer> </encryption>
</security>
<location-reference>L1</location-reference>
<access-diversity> <groups> <group>
<group-id>10</group-id> </group>
</groups> <constraints> <constraint>
<constraint-type>pop-diverse</constraint-type>
<target> <group> <group-id>20</group-id>
</group> </target> </constraint>
<constraint>
<constraint-type>linecard-diverse</constraint-type>
<target> <group> <group-id>10</group-id>
</group> </target> </constraint>
</constraints> </access-diversity>
<vpn-attachment> <vpn-id>VPNA</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
</site-network-accesses> </site> <site>
<site-id>Office3</site-id> <locations>
<location> <location-id>L1</location-id>
</location> </locations> <management>
<type>customer-managed</type> </management>
<security> <encryption>
<layer>layer3</layer> </encryption>
</security> <site-network-accesses>
<site-network-access>
<site-network-access-id>1</site-network-access-id>
<ip-connection> <ipv4>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv4> <ipv6>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv6> </ip-connection> <service>
<svc-mtu>1514</svc-mtu>
<svc-input-bandwidth>10000000</svc-input-bandwidth>
<svc-output-bandwidth>10000000</svc-output-bandwidth>
</service> <security> <encryption>
<layer>layer3</layer> </encryption>
</security>
<location-reference>L1</location-reference>
<access-diversity> <groups> <group>
<group-id>10</group-id> </group>
</groups> <constraints> <constraint>
<constraint-type>pop-diverse</constraint-type>
<target> <group> <group-id>20</group-id>
</group> </target> </constraint>
<constraint>
<constraint-type>linecard-diverse</constraint-type>
<target> <group> <group-id>10</group-id>
</group> </target> </constraint>
</constraints> </access-diversity>
<vpn-attachment> <vpn-id>VPNA</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
</site-network-accesses> </site> <site>
<site-id>Office4</site-id> <locations>
<location> <location-id>L1</location-id>
</location> </locations> <management>
<type>customer-managed</type> </management>
<security> <encryption>
<layer>layer3</layer> </encryption>
</security> <site-network-accesses>
<site-network-access>
<site-network-access-id>1</site-network-access-id>
<ip-connection> <ipv4>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv4> <ipv6>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv6> </ip-connection> <service>
<svc-mtu>1514</svc-mtu>
<svc-input-bandwidth>10000000</svc-input-bandwidth>
<svc-output-bandwidth>10000000</svc-output-bandwidth>
</service> <security> <encryption>
<layer>layer3</layer> </encryption>
</security>
<location-reference>L1</location-reference>
<access-diversity> <groups> <group>
<group-id>20</group-id> </group>
</groups> <constraints> <constraint>
<constraint-type>pop-diverse</constraint-type>
<target> <group> <group-id>10</group-id>
</group> </target> </constraint>
<constraint>
<constraint-type>linecard-diverse</constraint-type>
<target> <group> <group-id>20</group-id>
</group> </target> </constraint>
</constraints> </access-diversity>
<vpn-attachment> <vpn-id>VPNA</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
</site-network-accesses> </site> <site>
<site-id>Office5</site-id> <locations>
<location> <location-id>L1</location-id>
</location> </locations> <management>
<type>customer-managed</type> </management>
<security> <encryption>
<layer>layer3</layer> </encryption>
</security> <site-network-accesses>
<site-network-access>
<site-network-access-id>1</site-network-access-id>
<ip-connection> <ipv4>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv4> <ipv6>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv6> </ip-connection> <service>
<svc-mtu>1514</svc-mtu>
<svc-input-bandwidth>10000000</svc-input-bandwidth>
<svc-output-bandwidth>10000000</svc-output-bandwidth>
</service> <security> <encryption>
<layer>layer3</layer> </encryption>
</security>
<location-reference>L1</location-reference>
<access-diversity> <groups> <group>
<group-id>20</group-id> </group>
</groups> <constraints> <constraint>
<constraint-type>pop-diverse</constraint-type>
<target> <group> <group-id>10</group-id>
</group> </target> </constraint>
<constraint>
<constraint-type>linecard-diverse</constraint-type>
<target> <group> <group-id>20</group-id>
</group> </target> </constraint>
</constraints> </access-diversity>
<vpn-attachment> <vpn-id>VPNA</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
</site-network-accesses> </site> <site>
<site-id>Office6</site-id> <locations>
<location> <location-id>L1</location-id>
</location> </locations> <management>
<type>customer-managed</type> </management>
<security> <encryption>
<layer>layer3</layer> </encryption>
</security> <site-network-accesses>
<site-network-access>
<site-network-access-id>1</site-network-access-id>
<ip-connection> <ipv4>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv4> <ipv6>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv6> </ip-connection> <service>
<svc-mtu>1514</svc-mtu>
<svc-input-bandwidth>10000000</svc-input-bandwidth>
<svc-output-bandwidth>10000000</svc-output-bandwidth>
</service> <security> <encryption>
<layer>layer3</layer> </encryption>
</security>
<location-reference>L1</location-reference>
<access-diversity> <groups> <group>
<group-id>20</group-id> </group>
</groups> <constraints> <constraint>
<constraint-type>pop-diverse</constraint-type>
<target> <group> <group-id>10</group-id>
</group> </target> </constraint>
<constraint>
<constraint-type>linecard-diverse</constraint-type>
<target> <group> <group-id>20</group-id>
</group> </target> </constraint>
</constraints> </access-diversity>
<vpn-attachment> <vpn-id>VPNA</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
</site-network-accesses> </site> </sites>
</l3vpn-svc>
To increase its site bandwidth at lower cost, a customer wants to order two parallel site-network-accesses that will be connected to the same PE.
*******site-network-access#1**********
Site 1 *******site-network-access#2********** PE1
This scenario can be expressed with the following XML snippet:
<?xml version="1.0"?>
<l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-services> <vpn-service>
<vpn-id>VPNB</vpn-id> </vpn-service>
</vpn-services> <sites> <site>
<site-id>SITE1</site-id>
<site-network-accesses> <site-network-access>
<site-network-access-id>1</site-network-access-id>
<access-diversity> <groups> <group>
<group-id>PE-linkgrp-1</group-id> </group>
</groups> <constraints> <constraint>
<constraint-type>same-pe</constraint-type>
<target> <group>
<group-id>PE-linkgrp-1</group-id> </group>
</target> </constraint> </constraints>
</access-diversity> <vpn-attachment>
<vpn-id>VPNB</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
<site-network-access>
<site-network-access-id>2</site-network-access-id>
<access-diversity> <groups> <group>
<group-id>PE-linkgrp-1</group-id> </group>
</groups> <constraints> <constraint>
<constraint-type>same-pe</constraint-type>
<target> <group>
<group-id>PE-linkgrp-1</group-id> </group>
</target> </constraint> </constraints>
</access-diversity> <vpn-attachment>
<vpn-id>VPNB</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
</site-network-accesses> </site> </sites>
</l3vpn-svc>
A customer has a site that is dual-homed. The dual-homing must be done on two different PEs. The customer also wants to implement two subVPNs on those multihomed accesses.
+-----------------+ Site +------+ |
|---------------------------------/ +-----+ |
|****(site-network-access#1)*****| VPN B / \ | New York Office
|****(site-network-access#2)************| VPN C | | | +-----\ /
| | +-----+ | | | | +------+ | | / +-----+ |
|****(site-network-access#3)*****| VPN B / \ |
|****(site-network-access#4)************| VPN C | | | +-----\ /
| |----------------------------------- +-----+
+-----------------+
This scenario can be expressed as follows:
<?xml version="1.0"?>
<l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-services> <vpn-service>
<vpn-id>VPNB</vpn-id> </vpn-service>
<vpn-service> <vpn-id>VPNC</vpn-id>
</vpn-service> </vpn-services> <sites>
<site> <site-id>SITE1</site-id>
<locations> <location>
<location-id>L1</location-id> </location>
</locations> <management>
<type>customer-managed</type> </management>
<security> <encryption>
<layer>layer3</layer> </encryption>
</security> <site-network-accesses>
<site-network-access>
<site-network-access-id>1</site-network-access-id>
<ip-connection> <ipv4>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv4> <ipv6>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv6> </ip-connection> <service>
<svc-mtu>1514</svc-mtu>
<svc-input-bandwidth>10000000</svc-input-bandwidth>
<svc-output-bandwidth>10000000</svc-output-bandwidth>
</service> <security> <encryption>
<layer>layer3</layer> </encryption>
</security>
<location-reference>L1</location-reference>
<access-diversity> <groups> <group>
<group-id>dualhomed-1</group-id> </group>
</groups> <constraints> <constraint>
<constraint-type>pe-diverse</constraint-type>
<target> <group>
<group-id>dualhomed-2</group-id> </group>
</target> </constraint> <constraint>
<constraint-type>same-bearer</constraint-type>
<target> <group>
<group-id>dualhomed-1</group-id> </group>
</target> </constraint> </constraints>
</access-diversity> <vpn-attachment>
<vpn-id>VPNB</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
<site-network-access>
<site-network-access-id>2</site-network-access-id>
<access-diversity> <groups> <group>
<group-id>dualhomed-1</group-id> </group>
</groups> <constraints> <constraint>
<constraint-type>pe-diverse</constraint-type>
<target> <group>
<group-id>dualhomed-2</group-id> </group>
</target> </constraint> <constraint>
<constraint-type>same-bearer</constraint-type>
<target> <group>
<group-id>dualhomed-1</group-id> </group>
</target> </constraint> </constraints>
</access-diversity> <vpn-attachment>
<vpn-id>VPNC</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
<site-network-access>
<site-network-access-id>3</site-network-access-id>
<ip-connection> <ipv4>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv4> <ipv6>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv6> </ip-connection> <service>
<svc-mtu>1514</svc-mtu>
<svc-input-bandwidth>10000000</svc-input-bandwidth>
<svc-output-bandwidth>10000000</svc-output-bandwidth>
</service> <security> <encryption>
<layer>layer3</layer> </encryption>
</security>
<location-reference>L1</location-reference>
<access-diversity> <groups> <group>
<group-id>dualhomed-2</group-id> </group>
</groups> <constraints> <constraint>
<constraint-type>pe-diverse</constraint-type>
<target> <group>
<group-id>dualhomed-1</group-id> </group>
</target> </constraint> <constraint>
<constraint-type>same-bearer</constraint-type>
<target> <group>
<group-id>dualhomed-2</group-id> </group>
</target> </constraint> </constraints>
</access-diversity> <vpn-attachment>
<vpn-id>VPNB</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
<site-network-access>
<site-network-access-id>4</site-network-access-id>
<ip-connection> <ipv4>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv4> <ipv6>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv6> </ip-connection> <service>
<svc-mtu>1514</svc-mtu>
<svc-input-bandwidth>10000000</svc-input-bandwidth>
<svc-output-bandwidth>10000000</svc-output-bandwidth>
</service> <security> <encryption>
<layer>layer3</layer> </encryption>
</security>
<location-reference>L1</location-reference>
<access-diversity> <groups> <group>
<group-id>dualhomed-2</group-id> </group>
</groups> <constraints> <constraint>
<constraint-type>pe-diverse</constraint-type>
<target> <group>
<group-id>dualhomed-1</group-id> </group>
</target> </constraint> <constraint>
<constraint-type>same-bearer</constraint-type>
<target> <group>
<group-id>dualhomed-2</group-id> </group>
</target> </constraint> </constraints>
</access-diversity> <vpn-attachment>
<vpn-id>VPNC</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> </site-network-access>
</site-network-accesses> </site> </sites>
</l3vpn-svc>
The route distinguisher (RD) is a critical parameter of PE-based L3VPNs as described in [RFC4364] that provides the ability to distinguish common addressing plans in different VPNs. As for route targets (RTs), a management system is expected to allocate a VRF on the target PE and an RD for this VRF.
If a VRF already exists on the target PE and the VRF fulfills the connectivity constraints for the site, there is no need to recreate another VRF, and the site MAY be meshed within this existing VRF. How the management system checks that an existing VRF fulfills the connectivity constraints for a site is out of scope for this document.
If no such VRF exists on the target PE, the management system has to initiate the creation of a new VRF on the target PE and has to allocate a new RD for this new VRF.
The management system MAY apply a per-VPN or per-VRF allocation policy for the RD, depending on the SP's policy. In a per-VPN allocation policy, all VRFs (dispatched on multiple PEs) within a VPN will share the same RD value. In a per-VRF model, all VRFs should always have a unique RD value. Some other allocation policies are also possible, and this document does not restrict the allocation policies to be used.
The allocation of RDs MAY be done in the same way as RTs. The examples provided in Section 6.2.1.1 could be reused in this scenario.
Note that an SP MAY configure a target PE for an automated allocation of RDs. In this case, there will be no need for any backend system to allocate an RD value.
A site may be multihomed, meaning that it has multiple site-network-access points. Placement constraints defined in previous sections will help ensure physical diversity.
When the site-network-accesses are placed on the network, a customer may want to use a particular routing policy on those accesses.
The "site-network-access/availability" container defines parameters for site redundancy. The "access-priority" leaf defines a preference for a particular access. This preference is used to model load-balancing or primary/backup scenarios. The higher the access-priority value, the higher the preference will be.
The figure below describes how the access-priority attribute can be used.
Hub#1 LAN (Primary/backup) Hub#2 LAN
(Load-sharing) | | | access-priority 1 access-priority 1 | |--- CE1
------- PE1 PE3 --------- CE3 --- | | | | | |--- CE2 ------- PE2 PE4
--------- CE4 --- | | access-priority 2 access-priority 1 | PE5 | |
| CE5 | Spoke#1 site (Single-homed)
In the figure above, Hub#2 requires load-sharing, so all the site-network-accesses must use the same access-priority value. On the other hand, as Hub#1 requires a primary site-network-access and a backup site-network-access, a higher access-priority setting will be configured on the primary site-network-access.
Scenarios that are more complex can be modeled. Let's consider a Hub site with five accesses to the network (A1,A2,A3,A4,A5). The customer wants to load-share its traffic on A1,A2 in the nominal situation. If A1 and A2 fail, the customer wants to load-share its traffic on A3 and A4; finally, if A1 to A4 are down, he wants to use A5. We can model this easily by configuring the following access-priority values: A1=100, A2=100, A3=50, A4=50, A5=10.
The access-priority scenario has some limitations. An access-priority scenario like the previous one with five accesses but with the constraint of having traffic load-shared between A3 and A4 in the case where A1 OR A2 is down is not achievable. But the authors believe that using the access-priority attribute will cover most of the deployment use cases and that the model can still be extended via augmentation to support additional use cases.
The service model supports the ability to protect the traffic for a site. Such protection provides a better level of availability in multihoming scenarios by, for example, using local-repair techniques in case of failures. The associated level of service guarantee would be based on an agreement between the customer and the SP and is out of scope for this document.
Site#1 Site#2 CE1 ----- PE1 -- P1 P3 -- PE3
---- CE3 | | | | | | CE2 ----- PE2 -- P2 P4 -- PE4 ---- CE4 / / CE5
----+ Site#3
In the figure above, we consider an IP VPN service with three sites, including two dual-homed sites (Site#1 and Site#2). For dual-homed sites, we consider PE1-CE1 and PE3-CE3 as primary and PE2-CE2,PE4-CE4 as backup for the example (even if protection also applies to load-sharing scenarios).
In order to protect Site#2 against a failure, a user may set the "traffic-protection/enabled" leaf to true for Site#2. How the traffic protection will be implemented is out of scope for this document. However, in such a case, we could consider traffic coming from a remote site (Site#1 or Site#3), where the primary path would use PE3 as the egress PE. PE3 may have preprogrammed a backup forwarding entry pointing to the backup path (through PE4-CE4) for all prefixes going through the PE3-CE3 link. How the backup path is computed is out of scope for this document. When the PE3-CE3 link fails, traffic is still received by PE3, but PE3 automatically switches traffic to the backup entry; the path will therefore be PE1-P1-(...)-P3-PE3-PE4-CE4 until the remote PEs reconverge and use PE4 as the egress PE.
The "security" container defines customer-specific security parameters for the site. The security options supported in the model are limited but may be extended via augmentation.
The current model does not support any authentication parameters for the site connection, but such parameters may be added in the "authentication" container through augmentation.
Traffic encryption can be requested on the connection. It may be performed at Layer 2 or Layer 3 by selecting the appropriate enumeration in the "layer" leaf. For example, an SP may use IPsec when a customer requests Layer 3 encryption. The encryption profile can be SP defined or customer specific.
When an SP profile is used and a key (e.g., a pre-shared key) is allocated by the provider to be used by a customer, the SP should provide a way to communicate the key in a secured way to the customer.
When a customer profile is used, the model supports only a pre-shared key for authentication of the site connection, with the pre-shared key provided through the NETCONF or RESTCONF request. A secure channel must be used to ensure that the pre-shared key cannot be intercepted.
For security reasons, it may be necessary for the customer to change the pre-shared key on a regular basis. To perform a key change, the user can ask the SP to change the pre-shared key by submitting a new pre-shared key for the site configuration (as shown below with a corresponding XML snippet). This mechanism might not be hitless.
<?xml version="1.0"?> <l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-services> <vpn-service>
<vpn-id>VPNA</vpn-id> </vpn-service>
</vpn-services> <sites> <site>
<site-id>SITE1</site-id> <site-network-accesses>
<site-network-access>
<site-network-access-id>1</site-network-access-id>
<security> <encryption> <encryption-profile>
<preshared-key>MY_NEW_KEY</preshared-key>
</encryption-profile> </encryption> </security>
</site-network-access> </site-network-accesses>
</site> </sites> </l3vpn-svc>
A hitless key change mechanism may be added through augmentation.
Other key-management methodologies (e.g., PKI) may be added through augmentation.
The model defines three types of common management options:
Based on the management model, different security options MAY be derived.
In the co-managed case, the model defines options for the management address family (IPv4 or IPv6) and the associated management address.
"routing-protocol" defines which routing protocol must be activated between the provider and the customer router. The current model supports the following settings: bgp, rip, ospf, static, direct, and vrrp.
The routing protocol defined applies at the provider-to-customer boundary. Depending on how the management model is administered, it may apply to the PE-CE boundary or the CE-to-customer boundary. In the case of a customer-managed site, the routing protocol defined will be activated between the PE and the CE router managed by the customer. In the case of a provider-managed site, the routing protocol defined will be activated between the CE managed by the SP and the router or LAN belonging to the customer. In this case, we expect the PE-CE routing to be configured based on the SP's rules, as both are managed by the same entity.
Rtg protocol 192.0.2.0/24 ----- CE
----------------- PE1 Customer-managed site Rtg protocol Customer
router ----- CE ----------------- PE1 Provider-managed site
All the examples below will refer to a scenario for a customer- managed site.
All routing protocol types support dual stack by using the "address-family" leaf-list.
Example of a corresponding XML snippet with dual stack using the same routing protocol:
<?xml version="1.0"?> <l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-services> <vpn-service>
<vpn-id>VPNA</vpn-id> </vpn-service>
</vpn-services> <sites> <site>
<site-id>SITE1</site-id> <routing-protocols>
<routing-protocol> <type>static</type>
<static> <cascaded-lan-prefixes>
<ipv4-lan-prefixes> <lan>192.0.2.0/24</lan>
<next-hop>203.0.113.1</next-hop>
</ipv4-lan-prefixes> <ipv6-lan-prefixes>
<lan>2001:db8::1/64</lan>
<next-hop>2001:db8::2</next-hop>
</ipv6-lan-prefixes> </cascaded-lan-prefixes>
</static> </routing-protocol>
</routing-protocols> </site> </sites>
</l3vpn-svc>
Example of a corresponding XML snippet with dual stack using two different routing protocols:
<?xml version="1.0"?> <l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-services> <vpn-service>
<vpn-id>VPNA</vpn-id> </vpn-service>
</vpn-services> <sites> <site>
<site-id>SITE1</site-id> <routing-protocols>
<routing-protocol> <type>rip</type> <rip>
<address-family>ipv4</address-family> </rip>
</routing-protocol> <routing-protocol>
<type>ospf</type> <ospf>
<address-family>ipv6</address-family>
<area-address>4.4.4.4</area-address> </ospf>
</routing-protocol> </routing-protocols> </site>
</sites> </l3vpn-svc>
The routing protocol type "direct" SHOULD be used when a customer LAN is directly connected to the provider network and must be advertised in the IP VPN.
LAN attached directly to provider
network: 192.0.2.0/24 ----- PE1
In this case, the customer has a default route to the PE address.
The routing protocol type "vrrp" SHOULD be used and advertised in the IP VPN when
LAN attached directly to provider network with LAN redundancy:
192.0.2.0/24 ------ PE1 | +--- PE2
In this case, the customer has a default route to the SP network.
The routing protocol type "static" MAY be used when a customer LAN is connected to the provider network through a CE router and must be advertised in the IP VPN. In this case, the static routes give next hops (nh) to the CE and to the PE. The customer has a default route to the SP network.
Static rtg 192.0.2.0/24 ------ CE
-------------- PE | | | Static route 192.0.2.0/24 nh CE Static
route 0.0.0.0/0 nh PE
The routing protocol type "rip" MAY be used when a customer LAN is connected to the provider network through a CE router and must be advertised in the IP VPN. For IPv4, the model assumes that RIP version 2 is used.
In the case of dual-stack routing requested through this model, the management system will be responsible for configuring RIP (including the correct version number) and associated address families on network elements.
RIP rtg 192.0.2.0/24 ------ CE
-------------- PE
The routing protocol type "ospf" MAY be used when a customer LAN is connected to the provider network through a CE router and must be advertised in the IP VPN.
It can be used to extend an existing OSPF network and interconnect different areas. See [RFC4577] for more details.
+---------------------+ | | OSPF | | OSPF
area 1 | | area 2 (OSPF | | (OSPF area 1) --- CE ---------- PE PE
----- CE --- area 2) | | +---------------------+
The model also defines an option to create an OSPF sham link between two sites sharing the same area and having a backdoor link. The sham link is created by referencing the target site sharing the same OSPF area. The management system will be responsible for checking to see if there is already a sham link configured for this VPN and area between the same pair of PEs. If there is no existing sham link, the management system will provision one. This sham link MAY be reused by other sites.
+------------------------+ | | | | | PE
(--sham link--)PE | | | | | +----|----------------|--+ | OSPF area
1 | OSPF area 1 | | CE1 CE2 | | (OSPF area 1) (OSPF area 1) | |
+----------------+
Regarding dual-stack support, the user MAY specify both IPv4 and IPv6 address families, if both protocols should be routed through OSPF. As OSPF uses separate protocol instances for IPv4 and IPv6, the management system will need to configure both OSPF version 2 and OSPF version 3 on the PE-CE link.
Other OSPF parameters, such as timers, are typically set by the SP and communicated to the customer outside the scope of this model.
Example of a corresponding XML snippet with OSPF routing parameters in the service model:
<?xml version="1.0"?> <l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-services> <vpn-service>
<vpn-id>VPNA</vpn-id> </vpn-service>
</vpn-services> <sites> <site>
<site-id>SITE1</site-id> <routing-protocols>
<routing-protocol> <type>ospf</type>
<ospf> <area-address>0.0.0.1</area-address>
<address-family>ipv4</address-family>
<address-family>ipv6</address-family> </ospf>
</routing-protocol> </routing-protocols> </site>
</sites> </l3vpn-svc>
Example of PE configuration done by the management system:
router ospf 10 area 0.0.0.1 interface
Ethernet0/0 ! router ospfv3 10 area 0.0.0.1 interface Ethernet0/0
!
The routing protocol type "bgp" MAY be used when a customer LAN is connected to the provider network through a CE router and must be advertised in the IP VPN.
BGP rtg 192.0.2.0/24 ------ CE
-------------- PE
The session addressing will be derived from connection parameters as well as the SP's knowledge of the addressing plan that is in use.
In the case of dual-stack access, the user MAY request BGP routing for both IPv4 and IPv6 by specifying both address families. It will be up to the SP and management system to determine how to describe the configuration (two BGP sessions, single, multi-session, etc.). This, along with other BGP parameters such as timers, is communicated to the customer outside the scope of this model.
The service configuration below activates BGP on the PE-CE link for both IPv4 and IPv6.
BGP activation requires the SP to know the address of the customer peer. If the site-network-access connection addresses are used for BGP peering, the "static-address" allocation type for the IP connection MUST be used. Other peering mechanisms are outside the scope of this model. An example of a corresponding XML snippet is described as follows:
<?xml version="1.0"?> <l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-services> <vpn-service>
<vpn-id>VPNA</vpn-id> </vpn-service>
</vpn-services> <sites> <site>
<site-id>SITE1</site-id> <routing-protocols>
<routing-protocol> <type>bgp</type> <bgp>
<autonomous-system>65000</autonomous-system>
<address-family>ipv4</address-family>
<address-family>ipv6</address-family> </bgp>
</routing-protocol> </routing-protocols> </site>
</sites> </l3vpn-svc>
Depending on the SP flavor, a management system can divide this service configuration into different flavors, as shown by the following examples.
Example of PE configuration done by the management system (single IPv4 transport session):
router bgp 100 neighbor 203.0.113.2
remote-as 65000 address-family ipv4 vrf Cust1 neighbor 203.0.113.2
activate address-family ipv6 vrf Cust1 neighbor 203.0.113.2
activate neighbor 203.0.113.2 route-map SET-NH-IPV6 out
Example of PE configuration done by the management system (two sessions):
router bgp 100 neighbor 203.0.113.2
remote-as 65000 neighbor 2001::2 remote-as 65000 address-family
ipv4 vrf Cust1 neighbor 203.0.113.2 activate address-family ipv6
vrf Cust1 neighbor 2001::2 activate
Example of PE configuration done by the management system (multi-session):
router bgp 100 neighbor 203.0.113.2
remote-as 65000 neighbor 203.0.113.2 multisession per-af
address-family ipv4 vrf Cust1 neighbor 203.0.113.2 activate
address-family ipv6 vrf Cust1 neighbor 203.0.113.2 activate
neighbor 203.0.113.2 route-map SET-NH-IPV6 out
The service defines service parameters associated with the site.
The service bandwidth refers to the bandwidth requirement between the PE and the CE (WAN link bandwidth). The requested bandwidth is expressed as svc-input-bandwidth and svc-output-bandwidth in bits per second. The input/output direction uses the customer site as a reference: "input bandwidth" means download bandwidth for the site, and "output bandwidth" means upload bandwidth for the site.
The service bandwidth is only configurable at the site-network-access level.
Using a different input and output bandwidth will allow the SP to determine if the customer allows for asymmetric bandwidth access, such as ADSL. It can also be used to set rate-limiting in a different way for uploading and downloading on a symmetric bandwidth access.
The bandwidth is a service bandwidth expressed primarily as IP bandwidth, but if the customer enables MPLS for Carriers' Carriers (CsC), this becomes MPLS bandwidth.
The service MTU refers to the maximum PDU size that the customer may use. If the customer sends packets which are longer than the requested service MTU, the network may discard it (or for IPv4, fragment it).
The model defines QoS parameters in an abstracted way:
QoS classification rules are handled by the "qos-classification-policy" container. The qos-classification-policy container is an ordered list of rules that match a flow or application and set the appropriate target class of service (target-class-id). The user can define the match using an application reference or a flow definition that is more specific (e.g., based on Layer 3 source and destination addresses, Layer 4 ports, and Layer 4 protocol). When a flow definition is used, the user can employ a "target-sites" leaf-list to identify the destination of a flow rather than using destination IP addresses. In such a case, an association between the site abstraction and the IP addresses used by this site must be done dynamically. How this association is done is out of scope for this document. The association of a site to an IP VPN is done through the "vpn-attachment" container. Therefore the user can also employ "target-sites" leaf-list and "vpn-attachment" to identify the destination of a flow targeted to specific vpn service. A rule that does not have a match statement is considered a match-all rule. An SP may implement a default terminal classification rule if the customer does not provide it. It will be up to the SP to determine its default target class. The current model defines some applications, but new application identities may be added through augmentation. The exact meaning of each application identity is up to the SP, so it will be necessary for the SP to advise the customer on the usage of application matching.
Where the classification is done depends on the SP's implementation of the service, but classification concerns the flow coming from the customer site and entering the network.
Provider network
+-----------------------+ 192.0.2.0/24 198.51.100.0/24 ---- CE
--------- PE Traffic flow ---------->
In the figure above, the management system should implement the classification rule:
The figure below describes a sample service description of QoS classification for a site:
<?xml version="1.0"?>
<l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-services> <vpn-service>
<vpn-id>VPNA</vpn-id> </vpn-service>
</vpn-services> <sites> <site>
<site-id>SITE1</site-id> <service> <qos>
<qos-classification-policy> <rule>
<id>SvrA-http</id> <match-flow>
<ipv4-src-prefix>192.0.2.0/24</ipv4-src-prefix>
<ipv4-dst-prefix>203.0.113.1/32</ipv4-dst-prefix>
<l4-dst-port>80</l4-dst-port>
<protocol-type>tcp</protocol-type>
</match-flow>
<target-class-id>DATA2</target-class-id>
</rule> <rule> <id>SvrA-ftp</id>
<match-flow>
<ipv4-src-prefix>192.0.2.0/24</ipv4-src-prefix>
<ipv4-dst-prefix>203.0.113.1/32</ipv4-dst-prefix>
<l4-dst-port>21</l4-dst-port>
<protocol-field>tcp</protocol-field>
</match-flow>
<target-class-id>DATA2</target-class-id>
</rule> <rule> <id>p2p</id>
<match-application>p2p</match-application>
<target-class-id>DATA3</target-class-id>
</rule> <rule> <id>any</id>
<target-class-id>DATA1</target-class-id>
</rule> </qos-classification-policy> </qos>
</service> </site> </sites> </l3vpn-svc>
In the example above:
The order of rule list entries is defined by the user. The management system responsible for translating those rules in network element configuration MUST keep the same processing order in network element configuration.
The user can choose either a standard profile provided by the operator or a custom profile. The "qos-profile" container defines the traffic-scheduling policy to be used by the SP.
Provider network
+-----------------------+ 192.0.2.0/24 198.51.100.0/24 ---- CE
--------- PE \ / qos-profile
A custom QoS profile is defined as a list of classes of services and associated properties. The properties are:
In addition, due to network conditions, some constraints may not be completely fulfilled by the SP; in this case, the SP should advise the customer about the limitations. How this communication is done is out of scope for this document.
Example of service configuration using a standard QoS profile with the following corresponding XML snippet:
<?xml version="1.0"?>
<l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-profiles> <valid-provider-identifiers>
<qos-profile-identifier> <id>GOLD</id>
</qos-profile-identifier> <qos-profile-identifier>
<id>PLATINUM</id> </qos-profile-identifier>
</valid-provider-identifiers> </vpn-profiles>
<vpn-services> <vpn-service>
<vpn-id>VPNA</vpn-id> </vpn-service>
</vpn-services> <sites> <site>
<site-id>SITE1</site-id> <locations>
<location> <location-id>L1</location-id>
</location> </locations>
<site-network-accesses> <site-network-access>
<site-network-access-id>1245HRTFGJGJ154654</site-network-access-id>
<vpn-attachment> <vpn-id>VPNA</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> <ip-connection> <ipv4>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv4> <ipv6>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv6> </ip-connection> <security>
<encryption> <layer>layer3</layer>
</encryption> </security>
<location-reference>L1</location-reference>
<service>
<svc-input-bandwidth>100000000</svc-input-bandwidth>
<svc-output-bandwidth>100000000</svc-output-bandwidth>
<svc-mtu>1514</svc-mtu> <qos>
<qos-profile> <profile>PLATINUM</profile>
</qos-profile> </qos> </service>
<location-reference>L1</location-reference>
</site-network-access> <site-network-access>
<site-network-access-id>555555AAAA2344</site-network-access-id>
<vpn-attachment> <vpn-id>VPNA</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> <ip-connection> <ipv4>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv4> <ipv6>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv6> </ip-connection> <security>
<encryption> <layer>layer3</layer>
</encryption> </security>
<location-reference>L1</location-reference>
<service>
<svc-input-bandwidth>2000000</svc-input-bandwidth>
<svc-output-bandwidth>2000000</svc-output-bandwidth>
<svc-mtu>1514</svc-mtu> <qos>
<qos-profile> <profile>GOLD</profile>
</qos-profile> </qos> </service>
</site-network-access> </site-network-accesses>
</site> </sites> </l3vpn-svc>
Example of service configuration using a custom QoS profile with the following corresponding XML snippet:
<?xml version="1.0"?>
<l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-profiles> <valid-provider-identifiers>
<qos-profile-identifier> <id>GOLD</id>
</qos-profile-identifier> <qos-profile-identifier>
<id>PLATINUM</id> </qos-profile-identifier>
</valid-provider-identifiers> </vpn-profiles>
<vpn-services> <vpn-service>
<vpn-id>VPNA</vpn-id> </vpn-service>
</vpn-services> <sites> <site>
<site-id>SITE1</site-id> <locations>
<location> <location-id>L1</location-id>
</location> </locations>
<site-network-accesses> <site-network-access>
<site-network-access-id>Site1</site-network-access-id>
<location-reference>L1</location-reference>
<ip-connection> <ipv4>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv4> <ipv6>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv6> </ip-connection> <service>
<svc-mtu>1514</svc-mtu>
<svc-input-bandwidth>10000000</svc-input-bandwidth>
<svc-output-bandwidth>10000000</svc-output-bandwidth>
</service> <security> <encryption>
<layer>layer3</layer> </encryption>
</security>
<location-reference>L1</location-reference>
<vpn-attachment> <vpn-id>VPNA</vpn-id>
<site-role>spoke-role</site-role>
</vpn-attachment> <service>
<svc-input-bandwidth>100000000</svc-input-bandwidth>
<svc-output-bandwidth>100000000</svc-output-bandwidth>
<qos> <qos-profile> <classes> <class>
<class-id>REAL_TIME</class-id>
<direction>both</direction>
<rate-limit>10</rate-limit> <latency>
<use-lowest-latency/> </latency> <bandwidth>
<guaranteed-bw-percent>80</guaranteed-bw-percent>
</bandwidth> </class> <class>
<class-id>DATA1</class-id> <latency>
<latency-boundary>70</latency-boundary>
</latency> <bandwidth>
<guaranteed-bw-percent>80</guaranteed-bw-percent>
</bandwidth> </class> <class>
<class-id>DATA2</class-id> <latency>
<latency-boundary>200</latency-boundary>
</latency> <bandwidth>
<guaranteed-bw-percent>5</guaranteed-bw-percent>
<end-to-end/> </bandwidth> </class>
</classes> </qos-profile> </qos>
</service> </site-network-access>
</site-network-accesses> </site> </sites>
</l3vpn-svc>
The custom QoS profile for Site1 defines a REAL_TIME class with a latency constraint expressed as the lowest possible latency. It also defines two data classes -- DATA1 and DATA2. The two classes express a latency boundary constraint as well as a bandwidth reservation, as the REAL_TIME class is rate-limited to 10% of the service bandwidth (10% of 100 Mbps = 10 Mbps). In cases where congestion occurs, the REAL_TIME traffic can go up to 10 Mbps (let's assume that only 5 Mbps are consumed). DATA1 and DATA2 will share the remaining bandwidth (95 Mbps) according to their percentage. So, the DATA1 class will be served with at least 76 Mbps of bandwidth, while the DATA2 class will be served with at least 4.75 Mbps. The latency boundary information of the data class may help the SP define a specific buffer tuning or a specific routing within the network. The maximum percentage to be used is not limited by this model but MUST be limited by the management system according to the policies authorized by the SP.
The "multicast" container defines the type of site in the customer multicast service topology: source, receiver, or both. These parameters will help the management system optimize the multicast service. Users can also define the type of multicast relationship with the customer: router (requires a protocol such as PIM), host (IGMP or MLD), or both. An address family (IPv4, IPv6, or both) can also be defined.
In the case of CsC [RFC4364], a customer may want to build an MPLS service using an IP VPN to carry its traffic.
LAN customer1 | | CE1 | | -------------
(vrf_cust1) CE1_ISP1 | ISP1 POP | MPLS link | ------------- | (vrf
ISP1) PE1 (...) Provider backbone PE2 (vrf ISP1) | | ------------
| | MPLS link | ISP1 POP CE2_ISP1 (vrf_cust1) | ------------ | CE2
| LAN customer1
In the figure above, ISP1 resells an IP VPN service but has no core network infrastructure between its POPs. ISP1 uses an IP VPN as the core network infrastructure (belonging to another provider) between its POPs.
In order to support CsC, the VPN service must indicate MPLS support by setting the "carrierscarrier" leaf to true in the vpn-service list. The link between CE1_ISP1/PE1 and CE2_ISP1/PE2 must also run an MPLS signalling protocol. This configuration is done at the site level.
In the proposed model, LDP or BGP can be used as the MPLS signalling protocol. In the case of LDP, an IGP routing protocol MUST also be activated. In the case of BGP signalling, BGP MUST also be configured as the routing protocol.
If CsC is enabled, the requested "svc-mtu" leaf will refer to the MPLS MTU and not to the IP MTU.
The service model sometimes refers to external information through identifiers. As an example, to order a cloud-access to a particular cloud service provider (CSP), the model uses an identifier to refer to the targeted CSP. If a customer is directly using this service model as an API (through REST or NETCONF, for example) to order a particular service, the SP should provide a list of authorized identifiers. In the case of cloud-access, the SP will provide the associated identifiers for each available CSP. The same applies to other identifiers, such as std-qos-profile, OAM profile-name, and provider-profile for encryption.
How an SP provides the meanings of those identifiers to the customer is out of scope for this document.
An autonomous system (AS) is a single network or group of networks that is controlled by a common system administration group and that uses a single, clearly defined routing protocol. In some cases, VPNs need to span different ASes in different geographic areas or span different SPs. The connection between ASes is established by the SPs and is seamless to the customer. Examples include
NNIs (network-to-network interfaces) have to be defined to extend the VPNs across multiple ASes.
[RFC4364] defines multiple flavors of VPN NNI implementations. Each implementation has pros and cons; this topic is outside the scope of this document. For example, in an Inter-AS option A, autonomous system border router (ASBR) peers are connected by multiple interfaces with at least one of those interfaces spanning the two ASes while being present in the same VPN. In order for these ASBRs to signal unlabeled IP prefixes, they associate each interface with a VPN routing and forwarding (VRF) instance and a Border Gateway Protocol (BGP) session. As a result, traffic between the back-to-back VRFs is IP. In this scenario, the VPNs are isolated from each other, and because the traffic is IP, QoS mechanisms that operate on IP traffic can be applied to achieve customer service level agreements (SLAs).
-------- -------------- ----------- / \ / \
/ \ | Cloud | | | | | | Provider |-----NNI-----| |----NNI---| Data
Center | | #1 | | | | | \ / | | \ / -------- | | ----------- | |
-------- | My network | ----------- / \ | | / \ | Cloud | | | | | |
Provider |-----NNI-----| |---NNI---| L3VPN | | #2 | | | | Partner |
\ / | | | | -------- | | | | \ / | | -------------- \ / |
----------- | NNI | | ------------------- / \ | | | | | | | L3VPN
Partner | | | \ / -------------------
The figure above describes an SP network called "My network" that has several NNIs. This network uses NNIs to:
AS A AS B -------------------
------------------- / \ / \ | | | | | ++++++++ Inter-AS link
++++++++ | | + +_______________+ + | | + (VRF1)---(VPN1)----(VRF1)
+ | | + ASBR + + ASBR + | | + (VRF2)---(VPN2)----(VRF2) + | | +
+_______________+ + | | ++++++++ ++++++++ | | | | | | | | | | | |
| | ++++++++ Inter-AS link ++++++++ | | + +_______________+ + | |
+ (VRF1)---(VPN1)----(VRF1) + | | + ASBR + + ASBR + | | +
(VRF2)---(VPN2)----(VRF2) + | | + +_______________+ + | | ++++++++
++++++++ | | | | | | | | | \ / \ / -------------------
-------------------
In option A, the two ASes are connected to each other with physical links on ASBRs. For resiliency purposes, there may be multiple physical connections between the ASes. A VPN connection -- physical or logical (on top of physical) -- is created for each VPN that needs to cross the AS boundary, thus providing a back-to-back VRF model.
From a service model's perspective, this VPN connection can be seen as a site. Let's say that AS B wants to extend some VPN connections for VPN C on AS A. The administrator of AS B can use this service model to order a site on AS A. All connection scenarios could be realized using the features of the current model. As an example, the figure above shows two physical connections that have logical connections per VPN overlaid on them. This could be seen as a dual-homed subVPN scenario. Also, the administrator of AS B will be able to choose the appropriate routing protocol (e.g., E-BGP) to dynamically exchange routes between ASes.
This document assumes that the option A NNI flavor SHOULD reuse the existing VPN site modeling.
Example: a customer wants its CSP A to attach its virtual network N to an existing IP VPN (VPN1) that he has from L3VPN SP B.
CSP A L3VPN SP B -----------------
------------------- / \ / \ | | | | | | VM --| ++++++++ NNI
++++++++ |--- VPN1 | | + +_________+ + | Site#1 |
|--------(VRF1)---(VPN1)--(VRF1)+ | | | + ASBR + + ASBR + | | | +
+_________+ + | | | ++++++++ ++++++++ | | VM --| | | |--- VPN1 |
|Virtual | | | Site#2 | |Network | | | | VM --| | | |--- VPN1 | |
| | | Site#3 \ / \ / ----------------- ------------------- | |
VPN1 Site#4
To create the VPN connectivity, the CSP or the customer may use the L3VPN service model that SP B exposes. We could consider that, as the NNI is shared, the physical connection (bearer) between CSP A and SP B already exists. CSP A may request through a service model the creation of a new site with a single site-network-access (single-homing is used in the figure). As a placement constraint, CSP A may use the existing bearer reference it has from SP A to force the placement of the VPN NNI on the existing link. The XML snippet below illustrates a possible configuration request to SP B:
<?xml version="1.0"?> <l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-profiles> <valid-provider-identifiers>
<qos-profile-identifier> <id>GOLD</id>
</qos-profile-identifier> <qos-profile-identifier>
<id>PLATINUM</id> </qos-profile-identifier>
</valid-provider-identifiers> </vpn-profiles>
<vpn-services> <vpn-service>
<vpn-id>VPN1</vpn-id> </vpn-service>
</vpn-services> <sites> <site>
<site-id>CSP_A_attachment</site-id> <security>
<encryption> <layer>layer3</layer>
</encryption> </security> <locations>
<location> <location-id>L1</location-id>
</location> </locations> <locations>
<location> <location-id>1</location-id>
<city>NY</city>
<country-code>US</country-code> </location>
</locations>
<site-vpn-flavor>site-vpn-flavor-nni</site-vpn-flavor>
<routing-protocols> <routing-protocol>
<type>bgp</type> <bgp>
<autonomous-system>500</autonomous-system>
<address-family>ipv4</address-family> </bgp>
</routing-protocol> </routing-protocols>
<site-network-accesses> <site-network-access>
<site-network-access-id>CSP_A_VN1</site-network-access-id>
<location-reference>L1</location-reference>
<ip-connection> <ipv4>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv4> <ipv6>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv6> </ip-connection> <ip-connection>
<ipv4> <address-allocation-type> static-address
</address-allocation-type> <addresses>
<provider-address>203.0.113.1</provider-address>
<customer-address>203.0.113.2</customer-address>
<prefix-length>30</prefix-length> </addresses>
</ipv4> </ip-connection> <service>
<svc-input-bandwidth>450000000</svc-input-bandwidth>
<svc-output-bandwidth>450000000</svc-output-bandwidth>
<svc-mtu>1514</svc-mtu> </service>
<security> <encryption>
<layer>layer3</layer> </encryption>
</security> <vpn-attachment>
<vpn-id>VPN1</vpn-id>
<site-role>any-to-any-role</site-role>
</vpn-attachment> </site-network-access>
</site-network-accesses> <management>
<type>customer-managed</type> </management>
</site> </sites> </l3vpn-svc>
The case described above is different from a scenario using the cloud-accesses container, as the cloud-access provides a public cloud access while this example enables access to private resources located in a CSP network.
AS A AS B -------------------
------------------- / \ / \ | | | | | ++++++++ Inter-AS link
++++++++ | | + +_______________+ + | | + + + + | | + ASBR
+<---MP-BGP---->+ ASBR + | | + + + + | | + +_______________+
+ | | ++++++++ ++++++++ | | | | | | | | | | | | | | ++++++++
Inter-AS link ++++++++ | | + +_______________+ + | | + + + + | | +
ASBR +<---MP-BGP---->+ ASBR + | | + + + + | | +
+_______________+ + | | ++++++++ ++++++++ | | | | | | | | | \ / \
/ ------------------- -------------------
In option B, the two ASes are connected to each other with physical links on ASBRs. For resiliency purposes, there may be multiple physical connections between the ASes. The VPN "connection" between ASes is done by exchanging VPN routes through MP-BGP [RFC4760].
There are multiple flavors of implementations of such an NNI. For example:
Case 1 does not require any service modeling, as the protocol enables the dynamic exchange of necessary VPN routes.
Case 2 requires that an RT-filtering policy on ASBRs be maintained. From a service modeling point of view, it is necessary to agree on the list of RTs to authorize.
In Case 3, both ASes need to agree on the VPN RT to exchange, as well as how to map a VPN RT from AS A to the corresponding RT in AS B (and vice versa).
Those modelings are currently out of scope for this document.
CSP A L3VPN SP B -----------------
------------------ / \ / \ | | | | | | VM --| ++++++++ NNI
++++++++ |--- VPN1 | | + +__________+ + | Site#1 | |-------+ + + +
| | | + ASBR +<-MP-BGP->+ ASBR + | | | + +__________+ + | |
| ++++++++ ++++++++ | | VM --| | | |--- VPN1 | |Virtual | | |
Site#2 | |Network | | | | VM --| | | |--- VPN1 | | | | | Site#3 \
/ | | ----------------- | | \ / ------------------ | | VPN1 Site#4
The example above describes an NNI connection between CSP A and SP network B. Both SPs do not trust themselves and use a different RT allocation policy. So, in terms of implementation, the customer VPN has a different RT in each network (RT A in CSP A and RT B in SP network B). In order to connect the customer virtual network in CSP A to the customer IP VPN (VPN1) in SP network B, CSP A should request that SP network B open the customer VPN on the NNI (accept the appropriate RT). Who does the RT translation depends on the agreement between the two SPs: SP B may permit CSP A to request VPN (RT) translation.
AS A AS B -------------------
------------------- / \ / \ | | | | | | | | | | | | | ++++++++
Multihop E-BGP ++++++++ | | + + + + | | + + + + | | + RGW
+<----MP-BGP---->+ RGW + | | + + + + | | + + + + | |
++++++++ ++++++++ | | | | | | | | | | | | | | | | | | | | | |
++++++++ Inter-AS link ++++++++ | | + +_______________+ + | | + +
+ + | | + ASBR + + ASBR + | | + + + + | | + +_______________+ + |
| ++++++++ ++++++++ | | | | | | | | | | | | | | ++++++++ Inter-AS
link ++++++++ | | + +_______________+ + | | + + + + | | + ASBR + +
ASBR + | | + + + + | | + +_______________+ + | | ++++++++ ++++++++
| | | | | | | | | \ / \ / ------------------- -------------------
From a VPN service's perspective, the option C NNI is very similar to option B, as an MP-BGP session is used to exchange VPN routes between the ASes. The difference is that the forwarding plane and the control plane are on different nodes, so the MP-BGP session is multihop between routing gateway (RGW) nodes.
From a VPN service's point of view, modeling options B and C will be identical.
As explained in Section 5, this service model is intended to be instantiated at a management layer and is not intended to be used directly on network elements. The management system serves as a central point of configuration of the overall service.
This section provides an example of how a management system can use this model to configure an IP VPN service on network elements.
In this example, we want to achieve the provisioning of a VPN service for three sites using a Hub-and-Spoke VPN service topology. One of the sites will be dual-homed, and load-sharing is expected.
+-------------------------------------------------------------+ |
Hub_Site ------ PE1 PE2 ------ Spoke_Site1 | | |
+----------------------------------+ | | | | |
+----------------------------------+ | Hub_Site ------ PE3 PE4 ------
Spoke_Site2 |
+-------------------------------------------------------------+
The following XML snippet describes the overall simplified service configuration of this VPN.
<?xml version="1.0"?> <l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-profiles> <valid-provider-identifiers>
<qos-profile-identifier> <id>GOLD</id>
</qos-profile-identifier> <qos-profile-identifier>
<id>PLATINUM</id> </qos-profile-identifier>
</valid-provider-identifiers> </vpn-profiles>
<vpn-services> <vpn-service>
<vpn-id>12456487</vpn-id>
<vpn-service-topology>hub-spoke</vpn-service-topology>
</vpn-service> </vpn-services> </l3vpn-svc>
When receiving the request for provisioning the VPN service, the management system will internally (or through communication with another OSS component) allocate VPN RTs. In this specific case, two RTs will be allocated (100:1 for Hub and 100:2 for Spoke). The output of corresponding XML snippet below describes the configuration of Spoke_Site1.
<?xml version="1.0"?> <l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-profiles> <valid-provider-identifiers>
<qos-profile-identifier> <id>GOLD</id>
</qos-profile-identifier> <qos-profile-identifier>
<id>PLATINUM</id> </qos-profile-identifier>
</valid-provider-identifiers> </vpn-profiles>
<vpn-services> <vpn-service>
<vpn-id>12456487</vpn-id>
<vpn-service-topology>hub-spoke</vpn-service-topology>
</vpn-service> </vpn-services> <sites> <site>
<site-id>Spoke_Site1</site-id> <devices>
<device> <device-id>D1</device-id> </device>
</devices> <locations> <location>
<location-id>1</location-id> <city>NY</city>
<country-code>US</country-code> </location>
</locations> <security> <encryption>
<layer>layer3</layer> </encryption>
</security> <routing-protocols> <routing-protocol>
<type>bgp</type> <bgp>
<autonomous-system>500</autonomous-system>
<address-family>ipv4</address-family>
<address-family>ipv6</address-family> </bgp>
</routing-protocol> </routing-protocols>
<site-network-accesses> <site-network-access>
<site-network-access-id>Spoke_Site1</site-network-access-id>
<device-reference>D1</device-reference>
<access-diversity> <groups> <group>
<group-id>20</group-id> </group> </groups>
<constraints> <constraint>
<constraint-type>pe-diverse</constraint-type>
<target> <group> <group-id>10</group-id>
</group> </target> </constraint>
</constraints> </access-diversity> <ip-connection>
<ipv4> <address-allocation-type> static-address
</address-allocation-type> <addresses>
<provider-address>203.0.113.254</provider-address>
<customer-address>203.0.113.2</customer-address>
<prefix-length>24</prefix-length> </addresses>
</ipv4> <ipv6> <address-allocation-type>
static-address </address-allocation-type> <addresses>
<provider-address>2001:db8::1</provider-address>
<customer-address>2001:db8::2</customer-address>
<prefix-length>64</prefix-length> </addresses>
</ipv6> </ip-connection> <service>
<svc-input-bandwidth>450000000</svc-input-bandwidth>
<svc-output-bandwidth>450000000</svc-output-bandwidth>
<svc-mtu>1514</svc-mtu> </service> <security>
<encryption> <layer>layer3</layer>
</encryption> </security> <vpn-attachment>
<vpn-id>12456487</vpn-id>
<site-role>spoke-role</site-role> </vpn-attachment>
</site-network-access> </site-network-accesses>
<management> <type>provider-managed</type>
</management> </site> </sites> </l3vpn-svc>
When receiving the request for provisioning Spoke_Site1, the management system MUST allocate network resources for this site. It MUST first determine the target network elements to provision the access, particularly the PE router (and perhaps also an aggregation switch). As described in Section 6.6, the management system SHOULD use the location information and MUST use the access-diversity constraint to find the appropriate PE. In this case, we consider that Spoke_Site1 requires PE diversity with the Hub and that the management system allocates PEs based on the least distance. Based on the location information, the management system finds the available PEs in the area nearest the customer and picks one that fits the access-diversity constraint.
When the PE is chosen, the management system needs to allocate interface resources on the node. One interface is selected from the pool of available PEs. The management system can start provisioning the chosen PE node via whatever means the management system prefers (e.g., NETCONF, CLI). The management system will check to see if a VRF that fits its needs is already present. If not, it will provision the VRF: the RD will be derived from the internal allocation policy model, and the RTs will be derived from the VPN policy configuration of the site (the management system allocated some RTs for the VPN). As the site is a Spoke site (site-role), the management system knows which RTs must be imported and exported. As the site is provider-managed, some management RTs may also be added (100:5000). Standard provider VPN policies MAY also be added in the configuration.
Example of generated PE configuration:
ip vrf Customer1 export-map
STD-CUSTOMER-EXPORT <---- Standard SP configuration
route-distinguisher 100:3123234324 route-target import 100:1
route-target import 100:5000 <---- Standard SP configuration
route-target export 100:2 for provider-managed CE !
When the VRF has been provisioned, the management system can start configuring the access on the PE using the allocated interface information. IP addressing is chosen by the management system. One address will be picked from an allocated subnet for the PE, and another will be used for the CE configuration. Routing protocols will also be configured between the PE and CE; because this model is provider-managed, the choices are left to the SP. BGP was chosen for this example. This choice is independent of the routing protocol chosen by the customer. BGP will be used to configure the CE-to-LAN connection as requested in the service model. Peering addresses will be derived from those of the connection. As the CE is provider- managed, the CE's AS number can be automatically allocated by the management system. Standard configuration templates provided by the SP may also be added.
Example of generated PE configuration:
interface Ethernet1/1/0.10 encapsulation
dot1q 10 ip vrf forwarding Customer1 ip address 198.51.100.1
255.255.255.252 <---- Comes from automated allocation ipv6 address
2001:db8::10:1/64 ip access-group STD-PROTECT-IN <---- Standard SP
config ! router bgp 100 address-family ipv4 vrf Customer1 neighbor
198.51.100.2 remote-as 65000 <---- Comes from automated allocation
neighbor 198.51.100.2 route-map STD in <---- Standard SP config
neighbor 198.51.100.2 filter-list 10 in <---- Standard SP config !
address-family ipv6 vrf Customer1 neighbor 2001:db8::0a10:2 remote-as
65000 <---- Comes from automated allocation neighbor
2001:db8::0a10:2 route-map STD in <---- Standard SP config neighbor
2001:db8::0a10:2 filter-list 10 in <---- Standard SP config ! ip
route vrf Customer1 192.0.2.1 255.255.255.255 198.51.100.2 ! Static
route for provider administration of CE !
As the CE router is not reachable at this stage, the management system can produce a complete CE configuration that can be manually uploaded to the node before sending the CE configuration to the customer premises. The CE configuration will be built in the same way as the PE would be configured. Based on the CE type (vendor/model) allocated to the customer as well as the bearer information, the management system knows which interface must be configured on the CE. PE-CE link configuration is expected to be handled automatically using the SP OSS, as both resources are managed internally. CE-to-LAN-interface parameters such as IP addressing are derived from the ip-connection container, taking into account how the management system distributes addresses between the PE and CE within the subnet. This will allow a plug-and-play configuration for the CE to be created.
Example of generated CE configuration:
interface Loopback10 description
"Administration" ip address 192.0.2.1 255.255.255.255 ! interface
FastEthernet10 description "WAN" ip address 198.51.100.2
255.255.255.252 <---- Comes from automated allocation ipv6 address
2001:db8::0a10:2/64 ! interface FastEthernet11 description "LAN" ip
address 203.0.113.254 255.255.255.0 <---- Comes from the
ip-connection container ipv6 address 2001:db8::1/64 ! router bgp 65000
address-family ipv4 redistribute static route-map STATIC2BGP <----
Standard SP configuration neighbor 198.51.100.1 remote-as 100 <----
Comes from automated allocation neighbor 203.0.113.2 remote-as 500
<---- Comes from the ip-connection container address-family ipv6
redistribute static route-map STATIC2BGP <---- Standard SP
configuration neighbor 2001:db8::0a10:1 remote-as 100 <---- Comes
from automated allocation neighbor 2001:db8::2 remote-as 500 <----
Comes from the ip-connection container ! route-map STATIC2BGP permit
10 match tag 10 !
As expressed in Section 5, this service model is intended to be instantiated in a management system and not directly on network elements.
The management system's role will be to configure the network elements. The management system may be modular, so the component instantiating the service model (let's call it "service component") and the component responsible for network element configuration (let's call it "configuration component") may be different.
l3vpn-svc | Model | | +---------------------+
| Service component | Service datastore +---------------------+ | |
+---------------------+ +----| Config component |------+ /
+---------------------+ \ Network / / \ \ Configuration / / \ \ models
/ / \ \ ++++++++ ++++++++ ++++++++ ++++++++ + CE A + ------- + PE A +
+ PE B + ----- + CE B + Config ++++++++ ++++++++ ++++++++ ++++++++
datastore Site A Site B
In the previous sections, we provided some examples of the translation of service provisioning requests to router configuration lines. In the NETCONF/YANG ecosystem, we expect NETCONF/YANG to be used between the configuration component and network elements to configure the requested services on those elements.
In this framework, specifications are expected to provide specific YANG modeling of service components on network elements. There will be a strong relationship between the abstracted view provided by this service model and the detailed configuration view that will be provided by specific configuration models for network elements.
The authors of this document anticipate definitions of YANG models for the network elements listed below. Note that this list is not exhaustive:
Example of a corresponding XML snippet with a VPN site request at the service level, using this model:
<?xml version="1.0"?> <l3vpn-svc
xmlns="urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc">
<vpn-profiles> <valid-provider-identifiers>
<qos-profile-identifier> <id>GOLD</id>
</qos-profile-identifier> <qos-profile-identifier>
<id>PLATINUM</id> </qos-profile-identifier>
</valid-provider-identifiers> </vpn-profiles>
<vpn-services> <vpn-service>
<vpn-id>VPN1</vpn-id>
<vpn-service-topology>hub-spoke</vpn-service-topology>
</vpn-service> </vpn-services> <sites> <site>
<site-id>Site A</site-id> <security>
<encryption> <layer>layer3</layer>
</encryption> </security> <locations>
<location> <location-id>L1</location-id>
</location> </locations> <site-network-accesses>
<site-network-access>
<site-network-access-id>1</site-network-access-id>
<ip-connection> <ipv4> <address-allocation-type>
static-address </address-allocation-type> <addresses>
<provider-address>203.0.113.254</provider-address>
<customer-address>203.0.113.2</customer-address>
<prefix-length>24</prefix-length> </addresses>
</ipv4> <ipv6>
<address-allocation-type>provider-dhcp</address-allocation-type>
</ipv6> </ip-connection> <service>
<svc-mtu>1514</svc-mtu>
<svc-input-bandwidth>10000000</svc-input-bandwidth>
<svc-output-bandwidth>10000000</svc-output-bandwidth>
</service>
<location-reference>L1</location-reference>
<vpn-attachment>
<vpn-policy-id>VPNPOL1</vpn-policy-id>
</vpn-attachment> </site-network-access>
</site-network-accesses> <routing-protocols>
<routing-protocol> <type>static</type>
<static> <cascaded-lan-prefixes> <ipv4-lan-prefixes>
<lan>198.51.100.0/30</lan>
<next-hop>203.0.113.2</next-hop>
</ipv4-lan-prefixes> </cascaded-lan-prefixes>
</static> </routing-protocol> </routing-protocols>
<management> <type>customer-managed</type>
</management> <vpn-policies> <vpn-policy>
<vpn-policy-id>VPNPOL1</vpn-policy-id> <entries>
<id>1</id> <vpn> <vpn-id>VPN1</vpn-id>
<site-role>any-to-any-role</site-role> </vpn>
</entries> </vpn-policy> </vpn-policies>
</site> </sites> </l3vpn-svc>
In the service example above, the service component is expected to request that the configuration component of the management system provide the configuration of the service elements. If we consider that the service component selected a PE (PE A) as the target PE for the site, the configuration component will need to push the configuration to PE A. The configuration component will use several YANG data models to define the configuration to be applied to PE A. The XML snippet configuration of PE A might look like this:
<if:interfaces> <if:interface>
<if:name>eth0</if:name>
<if:type>ianaift:ethernetCsmacd</if:type>
<if:description> Link to CE A. </if:description>
<ip:ipv4> <ip:address>
<ip:ip>203.0.113.254</ip:ip>
<ip:prefix-length>24</ip:prefix-length>
</ip:address> <ip:forwarding>true</ip:forwarding>
</ip:ipv4> </if:interface> </if:interfaces>
<rt:routing> <rt:routing-instance>
<rt:name>VRF_CustA</rt:name>
<rt:type>l3vpn-network:vrf</rt:type>
<rt:description>VRF for Customer A</rt:description>
<l3vpn-network:route-distinguisher> 100:1546542343
</l3vpn-network:route-distinguisher>
<l3vpn-network:import-rt>100:1</l3vpn-network:import-rt>
<l3vpn-network:export-rt>100:1</l3vpn-network:export-rt>
<rt:interfaces> <rt:interface>
<rt:name>eth0</rt:name> </rt:interface>
</rt:interfaces> <rt:routing-protocols>
<rt:routing-protocol> <rt:type>rt:static</rt:type>
<rt:name>st0</rt:name> <rt:static-routes>
<v4ur:ipv4> <v4ur:route> <v4ur:destination-prefix>
198.51.100.0/30 </v4ur:destination-prefix> <v4ur:next-hop>
<v4ur:next-hop-address> 203.0.113.2
</v4ur:next-hop-address> </v4ur:next-hop>
</v4ur:route> </v4ur:ipv4> </rt:static-routes>
</rt:routing-protocol> </rt:routing-protocols>
</rt:routing-instance> </rt:routing>
<CODE BEGINS>file
"ietf-l3vpn-svc@2017-10-11.yang" module ietf-l3vpn-svc { yang-version
1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc"; prefix
l3vpn-svc; import ietf-inet-types { prefix inet; } import
ietf-yang-types { prefix yang; } import ietf-netconf-acm { prefix
nacm; } organization "IETF L3SM Working Group"; contact "WG List:
<mailto:l3sm@ietf.org> Editor: L3SM WG Chairs: Adrian Farrel,
Qin Wu "; description "This YANG module defines a generic service
configuration model for Layer 3 VPNs. This model is common across all
vendor implementations."; revision 2017-10-11 { description "First
revision of RFC8049."; reference "RFC xxxx: YANG Data Model for L3VPN
Service Delivery"; } /* Features */ feature cloud-access { description
"Allows the VPN to connect to a CSP."; } feature multicast {
description "Enables multicast capabilities in a VPN."; } feature ipv4
{ description "Enables IPv4 support in a VPN."; } feature ipv6 {
description "Enables IPv6 support in a VPN."; } feature lan-tag {
description "Enables LAN Tag support in a VPN Policy Filter."; }
feature carrierscarrier { description "Enables support of CsC."; }
feature extranet-vpn { description "Enables support of extranet
VPNs."; } feature site-diversity { description "Enables support of
site diversity constraints."; } feature encryption { description
"Enables support of encryption."; } feature qos { description "Enables
support of classes of services."; } feature qos-custom { description
"Enables support of the custom QoS profile."; } feature rtg-bgp {
description "Enables support of the BGP routing protocol."; } feature
rtg-rip { description "Enables support of the RIP routing protocol.";
} feature rtg-ospf { description "Enables support of the OSPF routing
protocol."; } feature rtg-ospf-sham-link { description "Enables
support of OSPF sham links."; } feature rtg-vrrp { description
"Enables support of the VRRP routing protocol."; } feature
fast-reroute { description "Enables support of Fast Reroute."; }
feature bfd { description "Enables support of BFD."; } feature
always-on { description "Enables support of the 'always-on' access
constraint."; } feature requested-type { description "Enables support
of the 'requested-type' access constraint."; } feature
bearer-reference { description "Enables support of the
'bearer-reference' access constraint."; } feature target-sites {
description "Enables support of the 'target-sites' match flow
parameter."; } /* Typedefs */ typedef svc-id { type string;
description "Defines a type of service component identifier."; }
typedef template-id { type string; description "Defines a type of
service template identifier."; } typedef address-family { type
enumeration { enum ipv4 { description "IPv4 address family."; } enum
ipv6 { description "IPv6 address family."; } } description "Defines a
type for the address family."; } /* Identities */ identity
site-network-access-type { description "Base identity for
site-network-access type."; } identity point-to-point { base
site-network-access-type; description "Identity for point-to-point
connection."; } identity multipoint { base site-network-access-type;
description "Identity for multipoint connection. Example: Ethernet
broadcast segment."; } identity placement-diversity { description
"Base identity for site placement constraints."; } identity
bearer-diverse { base placement-diversity; description "Identity for
bearer diversity. The bearers should not use common elements."; }
identity pe-diverse { base placement-diversity; description "Identity
for PE diversity."; } identity pop-diverse { base placement-diversity;
description "Identity for POP diversity."; } identity linecard-diverse
{ base placement-diversity; description "Identity for linecard
diversity."; } identity same-pe { base placement-diversity;
description "Identity for having sites connected on the same PE."; }
identity same-bearer { base placement-diversity; description "Identity
for having sites connected using the same bearer."; } identity
customer-application { description "Base identity for customer
application."; } identity web { base customer-application; description
"Identity for Web application (e.g., HTTP, HTTPS)."; } identity mail {
base customer-application; description "Identity for mail
application."; } identity file-transfer { base customer-application;
description "Identity for file transfer application (e.g., FTP,
SFTP)."; } identity database { base customer-application; description
"Identity for database application."; } identity social { base
customer-application; description "Identity for social-network
application."; } identity games { base customer-application;
description "Identity for gaming application."; } identity p2p { base
customer-application; description "Identity for peer-to-peer
application."; } identity network-management { base
customer-application; description "Identity for management application
(e.g., Telnet, syslog, SNMP)."; } identity voice { base
customer-application; description "Identity for voice application."; }
identity video { base customer-application; description "Identity for
video conference application."; } identity embb { base
customer-application; description "Identity for enhanced Mobile
Broadband(eMBB) application. Note that eMBB application demands the
network performance with wide variety of characteristics such as data
rate, latency, loss rate, reliability and many other parameters."; }
identity urllc { base customer-application; description "Identity for
Ultra-Reliable and Low Latency Communications (URLLC) application.
Note that URLLC application demands the network performance with wide
variety of characteristics such as latency, reliability and many other
parameters."; } identity mmtc { base customer-application; description
"Identity for massive Machine Type Communications (mMTC) application.
Note that mMTC application demands the network performance with wide
variety of characteristics such as data rate, latency, loss rate,
reliability and many other parameters."; } identity site-vpn-flavor {
description "Base identity for the site VPN service flavor."; }
identity site-vpn-flavor-single { base site-vpn-flavor; description
"Base identity for the site VPN service flavor. Used when the site
belongs to only one VPN."; } identity site-vpn-flavor-multi { base
site-vpn-flavor; description "Base identity for the site VPN service
flavor. Used when a logical connection of a site belongs to multiple
VPNs."; } identity site-vpn-flavor-sub { base site-vpn-flavor;
description "Base identity for the site VPN service flavor. Used when
a site has multiple logical connections. Each connection may belong to
different multiple VPNs."; } identity site-vpn-flavor-nni { base
site-vpn-flavor; description "Base identity for the site VPN service
flavor. Used to describe an NNI option A connection."; } identity
management { description "Base identity for site management scheme.";
} identity co-managed { base management; description "Base identity
for co-managed site."; } identity customer-managed { base management;
description "Base identity for customer-managed site."; } identity
provider-managed { base management; description "Base identity for
provider-managed site."; } identity address-allocation-type {
description "Base identity for address-allocation-type for PE-CE
link."; } identity provider-dhcp { base address-allocation-type;
description "Provider network provides DHCP service to customer."; }
identity provider-dhcp-relay { base address-allocation-type;
description "Provider network provides DHCP relay service to
customer."; } identity provider-dhcp-slaac { base
address-allocation-type; description "Provider network provides DHCP
service to customer, as well as SLAAC."; } identity static-address {
base address-allocation-type; description "Provider-to-customer
addressing is static."; } identity slaac { base
address-allocation-type; description "Use IPv6 SLAAC."; } identity
site-role { description "Base identity for site type."; } identity
any-to-any-role { base site-role; description "Site in an any-to-any
IP VPN."; } identity spoke-role { base site-role; description "Spoke
site in a Hub-and-Spoke IP VPN."; } identity hub-role { base
site-role; description "Hub site in a Hub-and-Spoke IP VPN."; }
identity vpn-topology { description "Base identity for VPN topology.";
} identity any-to-any { base vpn-topology; description "Identity for
any-to-any VPN topology."; } identity hub-spoke { base vpn-topology;
description "Identity for Hub-and-Spoke VPN topology."; } identity
hub-spoke-disjoint { base vpn-topology; description "Identity for
Hub-and-Spoke VPN topology where Hubs cannot communicate with each
other."; } identity multicast-tree-type { description "Base identity
for multicast tree type."; } identity ssm-tree-type { base
multicast-tree-type; description "Identity for SSM tree type."; }
identity asm-tree-type { base multicast-tree-type; description
"Identity for ASM tree type."; } identity bidir-tree-type { base
multicast-tree-type; description "Identity for bidirectional tree
type."; } identity multicast-rp-discovery-type { description "Base
identity for RP discovery type."; } identity auto-rp { base
multicast-rp-discovery-type; description "Base identity for Auto-RP
discovery type."; } identity static-rp { base
multicast-rp-discovery-type; description "Base identity for static
type."; } identity bsr-rp { base multicast-rp-discovery-type;
description "Base identity for BSR discovery type."; } identity
routing-protocol-type { description "Base identity for routing
protocol type."; } identity ospf { base routing-protocol-type;
description "Identity for OSPF protocol type."; } identity bgp { base
routing-protocol-type; description "Identity for BGP protocol type.";
} identity static { base routing-protocol-type; description "Identity
for static routing protocol type."; } identity rip { base
routing-protocol-type; description "Identity for RIP protocol type.";
} identity vrrp { base routing-protocol-type; description "Identity
for VRRP protocol type. This is to be used when LANs are directly
connected to PE routers."; } identity direct { base
routing-protocol-type; description "Identity for direct protocol
type."; } identity protocol-type { description "Base identity for
protocol field type."; } identity tcp { base protocol-type;
description "TCP protocol type."; } identity udp { base protocol-type;
description "UDP protocol type."; } identity icmp { base
protocol-type; description "ICMP protocol type."; } identity icmp6 {
base protocol-type; description "ICMPv6 protocol type."; } identity
gre { base protocol-type; description "GRE protocol type."; } identity
ipip { base protocol-type; description "IP-in-IP protocol type."; }
identity hop-by-hop { base protocol-type; description "Hop-by-Hop IPv6
header type."; } identity routing { base protocol-type; description
"Routing IPv6 header type."; } identity esp { base protocol-type;
description "ESP header type."; } identity ah { base protocol-type;
description "AH header type."; } identity vpn-policy-filter-type {
description "Base identity for VPN Policy filter type."; } identity
ipv4 { base vpn-policy-filter-type; description "Identity for ipv4
prefix filter type."; } identity ipv6 { base vpn-policy-filter-type;
description "Identity for ipv6 prefix filter type."; } identity lan {
base vpn-policy-filter-type; description "Identity for lan tag filter
type."; } identity qos-profile-direction { description "Base identity
for qos profile direction."; } identity site-to-wan { base
qos-profile-direction; description "Identity for Site to WAN
direction."; } identity wan-to-site { base qos-profile-direction;
description "Identity for WAN to Site direction."; } identity both {
base qos-profile-direction; description "Identity for both WAN to Site
direction and Site to WAN direction."; } /* Groupings */ grouping
vpn-service-cloud-access { container cloud-accesses { if-feature
cloud-access; list cloud-access { key cloud-identifier; leaf
cloud-identifier { type leafref { path "/l3vpn-svc/vpn-profiles/"+
"valid-provider-identifiers/cloud-identifier/id"; } description
"Identification of cloud service. Local administration meaning."; }
choice list-flavor { case permit-any { leaf permit-any { type empty;
description "Allows all sites."; } } case deny-any-except { leaf-list
permit-site { type leafref { path "/l3vpn-svc/sites/site/site-id"; }
description "Site ID to be authorized."; } } case permit-any-except {
leaf-list deny-site { type leafref { path
"/l3vpn-svc/sites/site/site-id"; } description "Site ID to be
denied."; } } description "Choice for cloud access policy. By default,
all sites in the IP VPN MUST be authorized to access the cloud."; }
container address-translation { container nat44 { leaf enabled { type
boolean; default false; description "Controls whether or not Network
address translation from IPv4 to IPv4 (NAT44) [RFC3022]is required.";
} leaf nat44-customer-address { type inet:ipv4-address; description
"Address to be used for network address translation from IPv4 to IPv4.
This is to be used if the customer is providing the IPv4 address. If
customer address is not set, the model assumes that the provider will
allocate the address."; } description "IPv4-to-IPv4 translation."; }
description "Container for NAT."; } description "Cloud access
configuration."; } description "Container for cloud access
configurations."; } description "Grouping for VPN cloud definition.";
} grouping multicast-rp-group-cfg { choice group-format { mandatory
true; case singleaddress { leaf group-address { type inet:ip-address;
description "A Single Multicast Group address."; } } case startend {
leaf group-start { type inet:ip-address; description "The first
Multicast group address in the multicast group address range."; } leaf
group-end { type inet:ip-address; description "The last Multicast
group address in the multicast group address range."; } } description
"Choice for Multicast group format."; } description "This Grouping
defines Multicast Group or Multicast Groups for RP-to-group mapping.";
} grouping vpn-service-multicast { container multicast { if-feature
multicast; leaf enabled { type boolean; default false; description
"Enables multicast."; } container customer-tree-flavors { leaf-list
tree-flavor { type identityref { base multicast-tree-type; }
description "Type of tree to be used."; } description "Type of trees
used by customer."; } container rp { container rp-group-mappings {
list rp-group-mapping { key id; leaf id { type uint16; description
"Unique identifier for the mapping."; } container provider-managed {
leaf enabled { type boolean; default false; description "Set to true
if the Rendezvous Point (RP) must be a provider-managed node. Set to
false if it is a customer-managed node."; } leaf rp-redundancy { type
boolean; default false; description "If true, a redundancy mechanism
for the RP is required."; } leaf optimal-traffic-delivery { type
boolean; default false; description "If true, the SP must ensure that
traffic uses an optimal path, an SP may use Anycast RP or RP tree to
SPT switchover architectures."; } description "Parameters for a
provider-managed RP."; } leaf rp-address { when
"../provider-managed/enabled = 'false'" { description "Relevant when
the RP is not provider-managed."; } type inet:ip-address; mandatory
true; description "Defines the address of the RP. Used if the RP is
customer-managed."; } container groups { list group { key id; leaf id
{ type uint16; description "Identifier for the group."; } uses
multicast-rp-group-cfg; description "List of Multicast groups."; }
description "Multicast groups associated with the RP."; } description
"List of RP to group mappings."; } description "RP to group mappings
parameters."; } container rp-discovery { leaf rp-discovery-type { type
identityref { base multicast-rp-discovery-type; } default static-rp;
description "Type of RP discovery used."; } container bsr-candidates {
when "derived-from-or-self(../rp-discovery-type, "+
"'l3vpn-svc:bsr-rp')" { description "Only applicable if discovery type
is BSR-RP."; } leaf-list bsr-candidate-address { type inet:ip-address;
description "Address of BSR candidate."; } description "Container for
List of Customer BSR candidate's addresses."; } description "RP
discovery parameters."; } description "RP parameters."; } description
"Multicast global parameters for the VPN service."; } description
"Grouping for multicast VPN definition."; } grouping vpn-service-mpls
{ leaf carrierscarrier { if-feature carrierscarrier; type boolean;
default false; description "The VPN is using CsC, and so MPLS is
required."; } description "Grouping for MPLS CsC definition."; }
grouping customer-location-info { container locations { list location
{ key location-id; leaf location-id { type svc-id; description
"Identifier for a particular location."; } leaf address { type string;
description "Address (number and street) of the site."; } leaf
postal-code { type string; description "Postal code of the site."; }
leaf state { type string; description "State of the site. This leaf
can also be used to describe a region for a country that does not have
states."; } leaf city { type string; description "City of the site.";
} leaf country-code { type string { pattern '[A-Z]{2}'; } description
"Country of the site. Expressed as ISO ALPHA-2 code."; } description
"Location of the site."; } description "List of locations for the
site."; } description "This grouping defines customer location
parameters."; } grouping site-group { container groups { list group {
key group-id; leaf group-id { type string; description "Group-id the
site belongs to."; } description "List of group-ids."; } description
"Groups the site or site-network-access belongs to."; } description
"Grouping definition to assign group-ids to site or
site-network-access."; } grouping site-diversity { container
site-diversity { if-feature site-diversity; uses site-group;
description "Diversity constraint type. All site-network-accesses will
inherit the group values defined here."; } description "This grouping
defines site diversity parameters."; } grouping access-diversity {
container access-diversity { if-feature site-diversity; uses
site-group; container constraints { list constraint { key
constraint-type; leaf constraint-type { type identityref { base
placement-diversity; } description "Diversity constraint type."; }
container target { choice target-flavor { default id; case id { list
group { key group-id; leaf group-id { type string; description "The
constraint will be applied against this particular group-id for this
site network access level."; } description "List of group-ids
associated with one specific constraint for this site network access
level."; } } case all-accesses { leaf all-other-accesses { type empty;
description "The constraint will be applied against all other site
network accesses of this site."; } } case all-groups { leaf
all-other-groups { type empty; description "The constraint will be
applied against all other groups managed by the customer."; } }
description "Choice for the target flavor definition."; } description
"The constraint will be applied against Specific target, and the
target can be a list of group-ids,all other site network accesses of
this site or all other groups managed by the customer."; } description
"List of constraints."; } description "Placement constraints for this
site network access."; } description "Diversity parameters."; }
description "This grouping defines access diversity parameters."; }
grouping operational-requirements { leaf requested-site-start { type
yang:date-and-time; description "Optional leaf indicating requested
date and time when the service at a particular site is expected to
start."; } leaf requested-site-stop { type yang:date-and-time;
description "Optional leaf indicating requested date and time when the
service at a particular site is expected to stop."; } description
"This grouping defines some operational parameters."; } grouping
operational-requirements-ops { leaf actual-site-start { type
yang:date-and-time; config false; description "Optional leaf
indicating actual date and time when the service at a particular site
actually started."; } leaf actual-site-stop { type yang:date-and-time;
config false; description "Optional leaf indicating actual date and
time when the service at a particular site actually stopped."; }
description "This grouping defines some operational parameters."; }
grouping flow-definition { container match-flow { leaf dscp { type
inet:dscp; description "DSCP value."; } leaf dot1p { type uint8 {
range "0..7"; } description "802.1p matching."; } leaf ipv4-src-prefix
{ type inet:ipv4-prefix; description "Match on IPv4 src address."; }
leaf ipv6-src-prefix { type inet:ipv6-prefix; description "Match on
IPv6 src address."; } leaf ipv4-dst-prefix { type inet:ipv4-prefix;
description "Match on IPv4 dst address."; } leaf ipv6-dst-prefix {
type inet:ipv6-prefix; description "Match on IPv6 dst address."; }
leaf l4-src-port { type inet:port-number; must "current() <
../l4-src-port-range/lower-port or "+ "current() >
../l4-src-port-range/upper-port" { description "If l4-src-port and
l4-src-port-range/lower-port and upper-port are set at the same time,
l4-src-port should not overlap with l4-src-port-range. "; }
description "Match on Layer 4 src port."; } leaf-list target-sites {
if-feature target-sites; type svc-id; description "Identify a site as
traffic destination."; } container l4-src-port-range { leaf lower-port
{ type inet:port-number; description "Lower boundary for port."; }
leaf upper-port { type inet:port-number; must ". >= ../lower-port"
{ description " Upper boundary for port. If it exists, upper boundary
must be higher than lower boundary."; } description "Upper boundary
for port."; } description "Match on Layer 4 src port range. When only
lower-port is present, it represents a single port. When both
lower-port and upper-port are specified, it implies a range inclusive
of both values."; } leaf l4-dst-port { type inet:port-number; must
"current() < ../l4-dst-port-range/lower-port or "+ "current() >
../l4-dst-port-range/upper-port" { description " If l4-dst-port and
l4-dst-port-range/lower-port and upper-port are set at the same time,
l4-dst-port should not overlap with l4-src-port-range. "; }
description "Match on Layer 4 dst port."; } container
l4-dst-port-range { leaf lower-port { type inet:port-number;
description "Lower boundary for port."; } leaf upper-port { type
inet:port-number; must ". >= ../lower-port" { description "Upper
boundary must be higher than lower boundary."; } description "Upper
boundary for port. If it exists, upper boundary must be higher than
lower boundary."; } description "Match on Layer 4 dst port range. When
only lower-port is present, it represents a single port. When both
lower-port and upper-port are specified, it implies a range inclusive
of both values."; } leaf protocol-field { type union { type uint8;
type identityref { base protocol-type; } } description "Match on IPv4
protocol or IPv6 Next Header field."; } description "Describes
flow-matching criteria."; } description "Flow definition based on
criteria."; } grouping site-service-basic { leaf svc-input-bandwidth {
type uint64; units bps; mandatory true; description "From the customer
site's perspective, the service input bandwidth of the connection or
download bandwidth from the SP to the site."; } leaf
svc-output-bandwidth { type uint64; units bps; mandatory true;
description "From the customer site's perspective, the service output
bandwidth of the connection or upload bandwidth from the site to the
SP."; } leaf svc-mtu { type uint16; units bytes; mandatory true;
description "MTU at service level. If the service is IP, it refers to
the IP MTU. If CsC is enabled, the requested 'svc-mtu' leaf will refer
to the MPLS MTU and not to the IP MTU. "; } description "Defines basic
service parameters for a site."; } grouping site-protection {
container traffic-protection { if-feature fast-reroute; leaf enabled {
type boolean; default false; description "Enables traffic protection
of access link."; } description "Fast Reroute service parameters for
the site."; } description "Defines protection service parameters for a
site."; } grouping site-service-mpls { container carrierscarrier {
if-feature carrierscarrier; leaf signalling-type { type enumeration {
enum ldp { description "Use LDP as the signalling protocol between the
PE and the CE. In this case, an IGP routing protocol must also be
activated. "; } enum bgp { description "Use BGP (as per RFC 3107) as
the signalling protocol between the PE and the CE. In this case, BGP
must also be configured as the routing protocol."; } } default bgp;
description "MPLS signalling type."; } description "This container is
used when the customer provides MPLS-based services. This is only used
in the case of CsC(i.e., a customer builds an MPLS service using an IP
VPN to carry its traffic."; } description "Defines MPLS service
parameters for a site."; } grouping site-service-qos-profile {
container qos { if-feature qos; container qos-classification-policy {
list rule { key id; ordered-by user; leaf id { type string;
description "A description identifying qos classification policy
rule."; } choice match-type { default match-flow; case match-flow {
uses flow-definition; } case match-application { leaf
match-application { type identityref { base customer-application; }
description "Defines the application to match."; } } description
"Choice for classification."; } leaf target-class-id { type string;
description "Identification of the class of service. This identifier
is internal to the administration."; } description "List of marking
rules."; } description "Configuration of the traffic classification
policy."; } container qos-profile { choice qos-profile { description
"Choice for QoS profile. Can be standard profile or customized
profile."; case standard { description "Standard QoS profile."; leaf
profile { type leafref { path
"/l3vpn-svc/vpn-profiles/valid-provider-identifiers"+
"/qos-profile-identifier/id"; } description "QoS profile to be used.";
} } case custom { description "Customized QoS profile."; container
classes { if-feature qos-custom; list class { key class-id; leaf
class-id { type string; description "Identification of the class of
service. This identifier is internal to the administration."; } leaf
direction { type identityref { base qos-profile-direction; } default
both; description "The direction which QoS profile is applied to"; }
leaf rate-limit { type decimal64 { fraction-digits 5; range "0..100";
} units percent; description "To be used if the class must be
rate-limited. Expressed as percentage of the service bandwidth."; }
container latency { choice flavor { case lowest { leaf
use-lowest-latency { type empty; description "The traffic class should
use the path with the lowest latency."; } } case boundary { leaf
latency-boundary { type uint16; units msec; default 400; description
"The traffic class should use a path with a defined maximum latency.";
} } description "Latency constraint on the traffic class."; }
description "Latency constraint on the traffic class."; } container
jitter { choice flavor { case lowest { leaf use-lowest-jitter { type
empty; description "The traffic class should use the path with the
lowest jitter."; } } case boundary { leaf latency-boundary { type
uint32; units usec; default 40000; description "The traffic class
should use a path with a defined maximum jitter."; } } description
"Jitter constraint on the traffic class."; } description "Jitter
constraint on the traffic class."; } container bandwidth { leaf
guaranteed-bw-percent { type decimal64 { fraction-digits 5; range
"0..100"; } units percent; mandatory true; description "To be used to
define the guaranteed bandwidth as a percentage of the available
service bandwidth."; } leaf end-to-end { type empty; description "Used
if the bandwidth reservation must be done on the MPLS network too."; }
description "Bandwidth constraint on the traffic class."; }
description "List of classes of services."; } description "Container
for list of classes of services."; } } } description "QoS profile
configuration."; } description "QoS configuration."; } description
"This grouping defines QoS parameters for a site."; } grouping
site-security-authentication { container authentication { description
"Authentication parameters."; } description "This grouping defines
authentication parameters for a site."; } grouping
site-security-encryption { container encryption { if-feature
encryption; leaf enabled { type boolean; default false; description
"If true, traffic encryption on the connection is required."; } leaf
layer { when "../enabled = 'true'" { description " Require a value for
layer when enabled is true."; } type enumeration { enum layer2 {
description "Encryption will occur at Layer 2."; } enum layer3 {
description "Encryption will occur at Layer 3. For example, IPsec may
be used when a customer requests Layer 3 encryption."; } } description
"Layer on which encryption is applied."; } container
encryption-profile { choice profile { case provider-profile { leaf
profile-name { type leafref { path
"/l3vpn-svc/vpn-profiles/valid-provider-identifiers"+
"/encryption-profile-identifier/id"; } description "Name of the SP
profile to be applied."; } } case customer-profile { leaf algorithm {
type string; description "Encryption algorithm to be used."; } choice
key-type { default psk; case psk { leaf preshared-key { type string;
description " Pre-Shared Key(PSK) coming from customer."; } }
description "Type of keys to be used."; } } description "Choice of
encryption profile, the encryption profile can be provider profile or
customer profile."; } description "Profile of encryption to be
applied."; } description "Encryption parameters."; } description "This
grouping defines encryption parameters for a site."; } grouping
site-attachment-bearer { container bearer { container requested-type {
if-feature requested-type; leaf requested-type { type string;
description "Type of requested bearer: Ethernet, DSL, Wireless, etc.
Operator specific."; } leaf strict { type boolean; default false;
description "Defines whether requested-type is a preference or a
strict requirement."; } description "Container for requested-type."; }
leaf always-on { if-feature always-on; type boolean; default true;
description "Request for an always-on access type. For example, this
could mean no dial access type."; } leaf bearer-reference { if-feature
bearer-reference; type string; description "This is an internal
reference for the SP."; } description "Bearer-specific parameters. To
be augmented."; } description "Defines physical properties of a site
attachment."; } grouping site-routing { container routing-protocols {
list routing-protocol { key type; leaf type { type identityref { base
routing-protocol-type; } description "Type of routing protocol."; }
container ospf { when "derived-from-or-self(../type,
'l3vpn-svc:ospf')" { description "Only applies when protocol is
OSPF."; } if-feature rtg-ospf; leaf-list address-family { type
address-family; min-elements "1"; description "If OSPF is used on this
site, this node contains configured value. This node contains at least
one address family to be activated."; } leaf area-address { type
yang:dotted-quad; mandatory true; description "Area address."; } leaf
metric { type uint16; default 1; description "Metric of the PE-CE
link. It is used in the routing state calculation and path selection.
The default value is set to 1 assigned to the PE-CE link."; }
container sham-links { if-feature rtg-ospf-sham-link; list sham-link {
key target-site; leaf target-site { type svc-id; description "Target
site for the sham link connection. The site is referred to by its
ID."; } leaf metric { type uint16; default 1; description "Metric of
the sham link. It is used in the routing state calculation and path
selection. The default value is set to 1."; } description "Creates a
sham link with another site."; } description "List of sham links."; }
description "OSPF-specific configuration."; } container bgp { when
"derived-from-or-self(../type, 'l3vpn-svc:bgp')" { description "Only
applies when protocol is BGP."; } if-feature rtg-bgp; leaf
autonomous-system { type uint32; mandatory true; description "Customer
AS number in case the customer requests BGP routing."; } leaf-list
address-family { type address-family; min-elements "1"; description
"If BGP is used on this site, this node contains configured value.
This node contains at least one address family to be activated."; }
description "BGP-specific configuration."; } container static { when
"derived-from-or-self(../type, 'l3vpn-svc:static')" { description
"Only applies when protocol is static. BGP activation requires the SP
to know the address of the customer peer. When BGP is enabled, the
'static-address' allocation type for the IP connection MUST be used.";
} container cascaded-lan-prefixes { list ipv4-lan-prefixes {
if-feature ipv4; key "lan next-hop"; leaf lan { type inet:ipv4-prefix;
description "LAN prefixes."; } leaf lan-tag { type string; description
"Internal tag to be used in VPN policies."; } leaf next-hop { type
inet:ipv4-address; description "Next-hop address to use on the
customer side."; } description "List of LAN prefixes for the site."; }
list ipv6-lan-prefixes { if-feature ipv6; key "lan next-hop"; leaf lan
{ type inet:ipv6-prefix; description "LAN prefixes."; } leaf lan-tag {
type string; description "Internal tag to be used in VPN policies."; }
leaf next-hop { type inet:ipv6-address; description "Next-hop address
to use on the customer side."; } description "List of LAN prefixes for
the site."; } description "LAN prefixes from the customer."; }
description "Configuration specific to static routing."; } container
rip { when "derived-from-or-self(../type, 'l3vpn-svc:rip')" {
description "Only applies when protocol is RIP. For IPv4, the model
assumes that RIP version 2 is used."; } if-feature rtg-rip; leaf-list
address-family { type address-family; min-elements "1"; description
"If RIP is used on this site, this node contains configured value.This
node contains at least one address family to be activated."; }
description "Configuration specific to RIP routing."; } container vrrp
{ when "derived-from-or-self(../type, 'l3vpn-svc:vrrp')" { description
"Only applies when protocol is VRRP."; } if-feature rtg-vrrp;
leaf-list address-family { type address-family; min-elements "1";
description "If VRRP is used on this site, this node contains
configured value. This node contains at least one address family to be
activated. "; } description "Configuration specific to VRRP routing.";
} description "List of routing protocols used on the site. This list
can be augmented."; } description "Defines routing protocols."; }
description "Grouping for routing protocols."; } grouping
site-attachment-ip-connection { container ip-connection { container
ipv4 { if-feature ipv4; leaf address-allocation-type { type
identityref { base address-allocation-type; } must
"not(derived-from-or-self(current(), 'l3vpn-svc:slaac') or "+
"derived-from-or-self(current(), 'l3vpn-svc:provider-dhcp-slaac'))" {
error-message "SLAAC is only applicable to IPv6"; } description
"Defines how addresses are allocated. If there is no value for address
allocation type, then the ipv4 is not enabled."; } container
provider-dhcp { when "derived-from-or-self(../address-allocation-type,
"+ "'l3vpn-svc:provider-dhcp')" { description "Only applies when
addresses are allocated by DHCP."; } leaf provider-address { type
inet:ipv4-address; description "Address of provider side. If
provider-address is not specified, then prefix length should not be
specified as well,it also implies provider-dhcp allocation is not
enabled. If provider address is specified, then prefix length may or
may not be specified. "; } leaf prefix-length { type uint8 { range
"0..32"; } must "(../provider-address)" { error-message "if prefix
length is specified, provider-address must also be specified.";
description "if prefix length is specified, provider-address must also
be specified."; } description "Subnet prefix length expressed in bits.
If not specified, or specified as zero, this means the customer leaves
the actual prefix length value to the provider."; } choice
address-assign { default number; case number { leaf
number-of-dynamic-address { type uint16; default 1; description
"Describes the number of IP addresses the customer requires."; } }
case explicit { container customer-addresses { list address-group {
key "group-id"; leaf group-id { type string; description "Group-id for
the address range from start-address to end-address."; } leaf
start-address { type inet:ipv4-address; description "First address.";
} leaf end-address { type inet:ipv4-address; description "Last
address."; } description "Describes IP addresses allocated by DHCP.
When only start-address or only end-address is present, it represents
a single address. When both start-address and end-address are
specified, it implies a range inclusive of both addresses. If no
address is specified, it implies customer addresses group is not
supported."; } description "Container for customer addresses allocated
by DHCP."; } } description "Choice for the way to assign addresses.";
} description "DHCP allocated addresses related parameters."; }
container dhcp-relay { when
"derived-from-or-self(../address-allocation-type, "+
"'l3vpn-svc:provider-dhcp-relay')" { description "Only applies when
provider is required to implement DHCP relay function."; } leaf
provider-address { type inet:ipv4-address; description "Address of
provider side. If provider-address is not specified, then prefix
length should not be specified as well,it also implies provider-dhcp
allocation is not enabled. If provider address is specified, then
prefix length may or may not be specified."; } leaf prefix-length {
type uint8 { range "0..32"; } must "(../provider-address)" {
error-message "if prefix length is specified, provider-address must
also be specified."; description "if prefix length is specified,
provider-address must also be specified."; } description "Subnet
prefix length expressed in bits. If not specified, or specified as
zero,this means the customer leaves the actual prefix length value to
the provider."; } container customer-dhcp-servers { leaf-list
server-ip-address { type inet:ipv4-address; description "IP address of
customer DHCP server."; } description "Container for list of customer
DHCP servers."; } description "DHCP relay provided by operator."; }
container addresses { when
"derived-from-or-self(../address-allocation-type, "+
"'l3vpn-svc:static-address')" { description "Only applies when
protocol allocation type is static."; } leaf provider-address { type
inet:ipv4-address; description "IPv4 Address List of provider side.
When protocol allocation type is static, provider address must be
configured."; } leaf customer-address { type inet:ipv4-address;
description "IPv4 Address of customer side."; } leaf prefix-length {
type uint8 { range "0..32"; } description "Subnet prefix length
expressed in bits. It is applied to both provider-address and
customer-address."; } description "Describes IPv4 addresses used."; }
description "IPv4-specific parameters."; } container ipv6 { if-feature
ipv6; leaf address-allocation-type { type identityref { base
address-allocation-type; } description "Defines how addresses are
allocated. If there is no value for address allocation type, then the
ipv6 is not enabled."; } container provider-dhcp { when
"derived-from-or-self(../address-allocation-type,
'l3vpn-svc:provider-dhcp') "+ "or
derived-from-or-self(../address-allocation-type,
'l3vpn-svc:provider-dhcp-slaac')" { description "Only applies when
addresses are allocated by DHCP."; } leaf provider-address { type
inet:ipv6-address; description "Address of provider side. If
provider-address is not specified, then prefix length should not be
specified as well,it also implies provider-dhcp allocation is not
enabled. If provider address is specified, then prefix length may or
may not be specified."; } leaf prefix-length { type uint8 { range
"0..128"; } must "(../provider-address)" { error-message "if prefix
length is specified, provider-address must also be specified.";
description "if prefix length is specified, provider-address must also
be specified."; } description "Subnet prefix length expressed in bits.
If not specified, or specified as zero,this means the customer leaves
the actual prefix length value to the provider."; } choice
address-assign { default number; case number { leaf
number-of-dynamic-address { type uint16; default 1; description
"Describes the number of IP addresses the customer requires."; } }
case explicit { container customer-addresses { list address-group {
key "group-id"; leaf group-id { type string; description "Group-id for
the address range from start-address to end-address."; } leaf
start-address { type inet:ipv6-address; description "First address.";
} leaf end-address { type inet:ipv6-address; description "Last
address."; } description "Describes IP addresses allocated by DHCP.
When only start-address or only end-address is present, it represents
a single address. When both start-address and end-address are
specified, it implies a range inclusive of both addresses. If no
address is specified, it implies customer addresses group is not
supported."; } description "Container for customer addresses allocated
by DHCP."; } } description "Choice for the way to assign addresses.";
} description "DHCP allocated addresses related parameters."; }
container dhcp-relay { when
"derived-from-or-self(../address-allocation-type, "+
"'l3vpn-svc:provider-dhcp-relay')" { description "Only applies when
provider is required to implement DHCP relay function."; } leaf
provider-address { type inet:ipv6-address; description "Address of
provider side. If provider-address is not specified, then prefix
length should not be specified as well,it also implies provider-dhcp
allocation is not enabled. If provider address is specified, then
prefix length may or may not be specified."; } leaf prefix-length {
type uint8 { range "0..128"; } must "(../provider-address)" {
error-message "if prefix length is specified, provider-address must
also be specified."; description "if prefix length is specified,
provider-address must also be specified."; } description "Subnet
prefix length expressed in bits. If not specified, or specified as
zero, this means the customer leaves the actual prefix length value to
the provider."; } container customer-dhcp-servers { leaf-list
server-ip-address { type inet:ipv6-address; description "This node
contains IP address of customer DHCP server.If DHCP relay function is
implemented by the provider, this node contains the configured
value."; } description "Container for list of customer DHCP servers.";
} description "DHCP relay provided by operator."; } container
addresses { when "derived-from-or-self(../address-allocation-type, "+
"'l3vpn-svc:static-address')" { description "Only applies when
protocol allocation type is static."; } leaf provider-address { type
inet:ipv6-address; description "IPv6 Address of provider side. When
protocol allocation type is static, provider address must be
configured."; } leaf customer-address { type inet:ipv6-address;
description "IPv6 Address of customer side."; } leaf prefix-length {
type uint8 { range "0..128"; } description "Subnet prefix length
expressed in bits. It is applied to both provider-address and
customer-address."; } description "Describes IPv6 addresses used."; }
description "IPv6-specific parameters."; } container oam { container
bfd { if-feature bfd; leaf enabled { type boolean; default false;
description "If true, BFD activation is required."; } choice holdtime
{ default fixed; case fixed { leaf fixed-value { type uint32; units
msec; description "Expected BFD holdtime expressed in msec. The
customer may impose Some fixed values for the holdtime period if the
provider allows the customer use this function. If the provider
doesn't allow the customer use this function, the fixed-value will not
be set."; } } case profile { leaf profile-name { type leafref { path
"/l3vpn-svc/vpn-profiles/valid-provider-identifiers/"+
"bfd-profile-identifier/id"; } description "Well-known SP profile
Name. The provider can propose some profiles to the customer,
depending on the service level the customer wants to achieve. Profile
names must be communicated to the customer."; } description
"Well-known SP profile."; } description "Choice for holdtime flavor.";
} description "Container for BFD."; } description "Defines the OAM
mechanisms used on the connection. BFD is set as a fault detection
mechanism, but the 'oam' container can easily be augmented by other
mechanisms"; } description "Defines connection parameters."; }
description "This grouping defines IP connection parameters."; }
grouping site-service-multicast { container multicast { if-feature
multicast; leaf multicast-site-type { type enumeration { enum
receiver-only { description "The site only has receivers."; } enum
source-only { description "The site only has sources."; } enum
source-receiver { description "The site has both sources and
receivers."; } } default source-receiver; description "Type of
multicast site."; } container multicast-address-family { leaf ipv4 {
if-feature ipv4; type boolean; default false; description "Enables
IPv4 multicast."; } leaf ipv6 { if-feature ipv6; type boolean; default
false; description "Enables IPv6 multicast."; } description "Defines
protocol to carry multicast."; } leaf protocol-type { type enumeration
{ enum host { description "Hosts are directly connected to the
provider network. Host protocols such as IGMP or MLD are required."; }
enum router { description "Hosts are behind a customer router. PIM
will be implemented."; } enum both { description "Some hosts are
behind a customer router, and some others are directly connected to
the provider network.Both host and routing protocols must be used.
Typically, IGMP and PIM will be implemented."; } } default "both";
description "Multicast protocol type to be used with the customer
site."; } description "Multicast parameters for the site."; }
description "Multicast parameters for the site."; } grouping
site-management { container management { leaf type { type identityref
{ base management; } mandatory true; description "Management type of
the connection."; } description "Management configuration."; }
description "Management parameters for the site."; } grouping
site-devices { container devices { when
"derived-from-or-self(../management/type,
'l3vpn-svc:provider-managed') or "+
"derived-from-or-self(../management/type, 'l3vpn-svc:co-managed')" {
description "Applicable only for provider-managed or co-managed
device."; } list device { key device-id; leaf device-id { type svc-id;
description "Identifier for the device."; } leaf location { type
leafref { path "../../../locations/"+ "location/location-id"; }
mandatory true; description "Location of the device."; } container
management { when "derived-from-or-self(../../../management/type,"+
"'l3vpn-svc:co-managed')" { description "Applicable only for
co-managed device."; } leaf address-family { type address-family;
description "Address family used for management."; } leaf address {
when "(../address-family)" { description "If address-family is
specified, then address should also be specified.If address-family is
not specified, then address should also not be specified."; } type
inet:ip-address; mandatory true; description "Management address."; }
description "Management configuration. Applicable only for co-managed
device."; } description "List of devices requested by customer."; }
description "Device configuration."; } description "Grouping for
device allocation."; } grouping site-vpn-flavor { leaf site-vpn-flavor
{ type identityref { base site-vpn-flavor; } default
site-vpn-flavor-single; description "Defines the way the VPN
multiplexing is done ,e.g.,whether the site belongs to a single VPN
site or a multiVPN; In case of multiVPN, whether the logical accesses
of the sites belong to the same set of VPNs or each logical accesses
map to different VPNs. "; } description "Grouping for site VPN
flavor."; } grouping site-vpn-policy { container vpn-policies { list
vpn-policy { key vpn-policy-id; leaf vpn-policy-id { type svc-id;
description "Unique identifier for the VPN policy."; } list entries {
key id; leaf id { type svc-id; description "Unique identifier for the
policy entry."; } container filters { list filter { key type;
ordered-by user; leaf type { type identityref { base
vpn-policy-filter-type; } description "Type of VPN Policy filter."; }
leaf-list lan-tag { when "derived-from-or-self(../type,
'l3vpn-svc:lan')" { description "Only applies when VPN Policy filter
is LAN Tag filter."; } if-feature lan-tag; type string; description
"List of 'lan-tag' items to be matched. Lan-tag is Internal tag to be
used in VPN policies "; } leaf-list ipv4-lan-prefix { when
"derived-from-or-self(../type, 'l3vpn-svc:ipv4')" { description "Only
applies when VPN Policy filter is IPv4 Prefix filter."; } if-feature
ipv4; type inet:ipv4-prefix; description "List of IPv4 prefixes as LAN
Prefixes to be matched."; } leaf-list ipv6-lan-prefix { when
"derived-from-or-self(../type, 'l3vpn-svc:ipv6')" { description "Only
applies when VPN Policy filter is IPv6 Prefix filter."; } if-feature
ipv6; type inet:ipv6-prefix; description "List of IPv6 prefixes as LAN
prefixes to be matched."; } description "List of filters used on the
site. This list can be augmented."; } description "If a more-granular
VPN attachment is necessary, filtering can be used. If used, it
permits the splitting of site LANs among multiple VPNs.The Site LAN
can be split based on either LAN-tag or LAN prefix. If no filter is
used, all the LANs will be part of the same VPNs with the same role.";
} list vpn { key vpn-id; leaf vpn-id { type leafref { path
"/l3vpn-svc/vpn-services/"+ "vpn-service/vpn-id"; } mandatory true;
description "Reference to an IP VPN."; } leaf site-role { type
identityref { base site-role; } default any-to-any-role; description
"Role of the site in the IP VPN."; } description "List of VPNs the LAN
is associated with."; } description "List of entries for export
policy."; } description "List of VPN policies."; } description "VPN
policy."; } description "VPN policy parameters for the site."; }
grouping site-maximum-routes { container maximum-routes { list
address-family { key af; leaf af { type address-family; description
"Address family."; } leaf maximum-routes { type uint32; description
"Maximum prefixes the VRF can accept for this address family."; }
description "List of address families."; } description "Defines
'maximum-routes' for the VRF."; } description "Defines
'maximum-routes' for the site."; } grouping site-security { container
security { uses site-security-authentication; uses
site-security-encryption; description "Site-specific security
parameters."; } description "Grouping for security parameters."; }
grouping site-service { container service { uses
site-service-qos-profile; uses site-service-mpls; uses
site-service-multicast; description "Service parameters on the
attachment."; } description "Grouping for service parameters."; }
grouping site-network-access-service { container service { uses
site-service-basic; uses site-service-qos-profile; uses
site-service-mpls; uses site-service-multicast; description "Service
parameters on the attachment."; } description "Grouping for service
parameters."; } grouping vpn-extranet { container extranet-vpns {
if-feature extranet-vpn; list extranet-vpn { key vpn-id; leaf vpn-id {
type svc-id; description "Identifies the target VPN the local VPN want
to access."; } leaf local-sites-role { type identityref { base
site-role; } default any-to-any-role; description "This describes the
role of the local sites in the target VPN topology. In the any-to-any
VPN service topology, the local sites must have the same role, which
will be 'any-to-any-role '.In the Hub-and-Spoke VPN service topology
or the Hub and Spoke disjoint VPN service topology, the local sites
must have a Hub role or a Spoke role."; } description "List of
extranet VPNs or target VPNs the local VPN is attached to."; }
description "Container for extranet VPN configuration."; } description
"Grouping for extranet VPN configuration. This provides an easy way to
interconnect all sites from two VPNs."; } grouping
site-attachment-availability { container availability { leaf
access-priority { type uint32; default 100; description "Defines the
priority for the access. The higher the access-priority value, the
higher the preference of the access will be."; } description
"Availability parameters (used for multihoming)."; } description
"Defines availability parameters for a site."; } grouping
access-vpn-policy { container vpn-attachment { choice
attachment-flavor { case vpn-policy-id { leaf vpn-policy-id { type
leafref { path "../../../../"+ "vpn-policies/vpn-policy/"+
"vpn-policy-id"; } description "Reference to a VPN policy. When
referencing VPN policy for attachment, the vpn-policy-id must be
configured."; } } case vpn-id { leaf vpn-id { type leafref { path
"/l3vpn-svc/vpn-services"+ "/vpn-service/vpn-id"; } description
"Reference to a IP VPN. Referencing a vpn-id provides an easy way to
attach a particular logical access to a VPN. In this case, vpn-id must
be configured."; } leaf site-role { type identityref { base site-role;
} default any-to-any-role; description "Role of the site in the IP
VPN. When referencing a vpn-id, the site-role setting must be added to
express the role of the site in the target VPN service topology."; } }
mandatory true; description "Choice for VPN attachment flavor. A
choice is implemented to allow the user to choose the flavor that
provides the best fit."; } description "Defines VPN attachment of a
site."; } description "Defines the VPN attachment rules for a site's
logical access."; } grouping vpn-profile-cfg { container
valid-provider-identifiers { list cloud-identifier { if-feature
cloud-access; key id; leaf id { type string; description
"Identification of cloud service. Local administration meaning."; }
description "List for Cloud Identifiers."; } list
encryption-profile-identifier { key id; leaf id { type string;
description "Identification of the SP encryption profile to be used.
Local administration meaning."; } description "List for encryption
profile identifiers."; } list qos-profile-identifier { key id; leaf id
{ type string; description "Identification of the QoS Profile to be
used. Local administration meaning."; } description "List for QoS
Profile Identifiers."; } list bfd-profile-identifier { key id; leaf id
{ type string; description "Identification of the SP BFD Profile to be
used. Local administration meaning."; } description "List for BFD
profile Identifiers."; } nacm:default-deny-write; description
"Container for Valid Provider Identifies."; } description "Grouping
for VPN Profile configuration."; } grouping vpn-svc-cfg { leaf vpn-id
{ type svc-id; description "VPN identifier. Local administration
meaning."; } leaf customer-name { type string; description "Name of
the customer which actually uses vpn service. In the case that any
intermediary (e.g. Tier-2 provider or partner) sells the vpn service
to their enduser on behalf of the original service provider (e.g.
Tier-1 provider), the original service provider may require the
customer name to provide smooth activation/commitioning and operation
for the service."; } leaf vpn-service-topology { type identityref {
base vpn-topology; } default any-to-any; description "VPN service
topology."; } uses vpn-service-cloud-access; uses
vpn-service-multicast; uses vpn-service-mpls; uses vpn-extranet;
description "Grouping for VPN service configuration."; } grouping
site-top-level-cfg { uses operational-requirements; uses
customer-location-info; uses site-devices; uses site-diversity; uses
site-management; uses site-vpn-policy; uses site-vpn-flavor; uses
site-maximum-routes; uses site-security; uses site-service; uses
site-protection; uses site-routing; description "Grouping for site
top-level configuration."; } grouping
site-network-access-top-level-cfg { leaf site-network-access-type {
type identityref { base site-network-access-type; } default
point-to-point; description "Describes the type of connection, e.g.,
point-to-point or multipoint."; } choice location-flavor { case
location { when "derived-from-or-self(../../management/type, "+
"'l3vpn-svc:customer-managed')" { description "Applicable only for
customer-managed device."; } leaf location-reference { type leafref {
path "../../../locations/location/location-id"; } description
"Location of the site-network-access."; } } case device { when
"derived-from-or-self(../../management/type, "+
"'l3vpn-svc:provider-managed') or "+
"derived-from-or-self(../../management/type, "+
"'l3vpn-svc:co-managed')" { description "Applicable only for
provider-managed or co-managed device."; } leaf device-reference {
type leafref { path "../../../devices/device/device-id"; } description
"Identifier of CE to use."; } } mandatory true; description "Choice of
how to describe the site's location."; } uses access-diversity; uses
site-attachment-bearer; uses site-attachment-ip-connection; uses
site-security; uses site-network-access-service; uses site-routing;
uses site-attachment-availability; uses access-vpn-policy; description
"Grouping for site network access top-level configuration."; } /* Main
blocks */ container l3vpn-svc { container vpn-profiles { uses
vpn-profile-cfg; description "Container for VPN Profiles."; }
container vpn-services { list vpn-service { key vpn-id; uses
vpn-svc-cfg; description "List of VPN services."; } description
"Top-level container for the VPN services."; } container sites { list
site { key site-id; leaf site-id { type svc-id; description
"Identifier of the site."; } uses site-top-level-cfg; uses
operational-requirements-ops; container site-network-accesses { list
site-network-access { key site-network-access-id; leaf
site-network-access-id { type svc-id; description "Identifier for the
access."; } uses site-network-access-top-level-cfg; description "List
of accesses for a site."; } description "List of accesses for a
site."; } description "List of sites."; } description "Container for
sites."; } description "Main container for L3VPN service
configuration."; } } <CODE ENDS>
The YANG module defined in this document MAY be accessed via the RESTCONF protocol [RFC8040] or the NETCONF protocol [RFC6241]. The lowest RESTCONF or NETCONF layer requires that the transport-layer protocol provide both data integrity and confidentiality; see Section 2 in [RFC8040] and Section 2 in [RFC6241]. The client MUST carefully examine the certificate presented by the server to determine if it meets the client's expectations, and the server MUST authenticate client and authorize access to any protected resource. The client identity derived from the authentication mechanism used is subject to the NETCONF Access Control Model (NACM) [RFC6536]. Other protocols that are used to access this YANG module are also required to support similar security mechanisms.
The data nodes defined in the "ietf-l3vpn-svc" YANG module MUST be carefully created, read, updated, or deleted as appropriate which indirectly lead to creation or modification of the network. The entries in the lists below include customer-proprietary or confidential information,e.g.,customer-name; therefore, access to confidential information MUST be limited to authorized clients, and other clients MUST NOT be permitted to access the information.
The data model defines some security parameters than can be extended via augmentation as part of the customer service request; those parameters are described in Section 6.9.
IANA has assigned a new URI from the "IETF XML Registry" [RFC3688].
URI:
urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc Registrant Contact: The
IESG XML: N/A; the requested URI is an XML namespace.
IANA has recorded a YANG module name in the "YANG Module Names" registry [RFC7950] as follows:
Name: ietf-l3vpn-svc Namespace:
urn:ietf:params:xml:ns:yang:ietf-l3vpn-svc Prefix: l3vpn-svc
Reference: RFC 8049
IANA is requested to update this registry to reference this document on publication as an RFC.
| [I-D.ietf-netmod-acl-model] | Jethanandani, M., Huang, L., Agarwal, S. and D. Blair, "Network Access Control List (ACL) YANG Data Model", Internet-Draft draft-ietf-netmod-acl-model-14, October 2017. |
| [RFC4026] | Andersson, L. and T. Madsen, "Provider Provisioned Virtual Private Network (VPN) Terminology", RFC 4026, DOI 10.17487/RFC4026, March 2005. |
| [RFC4110] | Callon, R. and M. Suzuki, "A Framework for Layer 3 Provider-Provisioned Virtual Private Networks (PPVPNs)", RFC 4110, DOI 10.17487/RFC4110, July 2005. |
| [RFC4760] | Bates, T., Chandra, R., Katz, D. and Y. Rekhter, "Multiprotocol Extensions for BGP-4", RFC 4760, DOI 10.17487/RFC4760, January 2007. |
Maxim Klyus, Luis Miguel Contreras, Gregory Mirsky, Zitao Wang, Jing Zhao, Kireeti Kompella, Eric Rosen, Aijun Wang,Michael Scharf, Xufeng Liu, David Ball, Lucy Yong, Jean-Philippe Landry, and Andrew Leu provided useful review to this document.
Jan Lindblad reviewed the first release of RFC8049 and found some bugs and His thorough YANG Doctor review on the YANG Model is valuable input to revision of RFC8049. David ball also provided a second review on published RFC8049.
Many thanks to these people.
The authors would like to thank Rob Shakir for his major contributions to the initial modeling and use cases.
Adrian Farrel prepared the editorial revisions for this bis.