| BESS Working Group | M. Wang |
| Internet-Draft | Q. Wu |
| Intended status: Standards Track | R. Even |
| Expires: January 9, 2020 | Huawei |
| B. Wen | |
| Comcast | |
| C. Liu | |
| China Unicom | |
| July 8, 2019 |
A YANG Model for Network and VPN Service Performance Monitoring
draft-www-bess-yang-vpn-service-pm-03
The data model defined in [RFC8345] introduces vertical layering relationships between networks that can be augmented to cover network/service topologies. This document defines a YANG model for Network and VPN Service Performance Monitoring that can be used to monitor and manage network performance on the topology at different layer or the overlay topology between VPN sites. This model is an augmentation to the network topology YANG data model defined in [RFC8345].
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 January 9, 2020.
Copyright (c) 2019 IETF Trust and the persons identified as the document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.
[RFC8345] defines an abstract YANG data model for network/service topologies and inventories. Service topology in [RFC8345] includes the a virtual topology for a service layer above the L1, L2, and L3 layers. This virtual topology has the generic topology elements of node, link, and terminating point. One typical example of a service topology is described in figure 3 of [RFC8345], two VPN service topologies instantiated over a common L3 topology. Each VPN service topology is mapped onto a subset of nodes from the common L3 topology.
In [RFC8299], 3 types of VPN service topologies are defined for the L3VPN service data model: any to any; hub and spoke; and hub and spoke disjoint. These VPN topology types can be used to describe how VPN sites communicate with each other.
This document defines a YANG Model for Network performance monitoring and VPN Service Performance Monitoring that can be used to monitor and manage network Performance on the topology at different layer or the overlay topology between VPN sites and it is an augmentation to the network topology YANG data model defined in [RFC8345].
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119]. In this document, these words will appear with that interpretation only when in ALL CAPS. Lower case uses of these words are not to be interpreted as carrying [RFC2119] significance.
Tree diagrams used in this document follow the notation defined in [RFC8340].
This module describes Network and VPN Service assurance that can be used to monitor and manage the network Performance in the underlying network or between VPN sites and it is a augmentation to the "ietf-network" and "ietf-network-topology" YANG data model [RFC8345]. The performance monitoring data is augmented to service topology.
+----------------------+ +-----------------------+
|ietf-network | |Network and VPN Service|
|ietf-network-topology |<---------|Peformance Monitoring |
+----------------------+ augments | Model |
+-----------------------+
+----:--------------:----:--------------+
/ : : : "L3" /
/ : : : /
/ : : : /
/ [Y1]_____________[Y2] /
/ * * * /
/ * * * /
+--------------*-------------*--*-------+
* * *
+--------*----------*----*--------------+
/ [Z1]_______________[Z2] "Optical" /
/ \_ * _/ /
/ \_ * _/ /
/ \_ * _/ /
/ \ * / /
/ [Z] /
+---------------------------------------+
Example of Layering relationship between the L3 Topology and the Optical topology
The data model defined in [RFC8345] can describe vertical layering relationships between networks. That model can be augmented to cover network/service topologies. Figure 1 describes an example on layering relationship between L3 topology and the Optical topology:
Figure 2 describes another example on relationships between the L3VPN service topology and the underlying network:
VPN-SVC 1 VPN-SVC 2
/ \
L3VPN-Service-topology 1 L3VPN-Service-topology-2
/ | \ / | \
Site-1A Site-1B Site1-C Site-2A Site-2B Site-2C Top-Down
| | | | | | Service Topology
CE CE CE CE CE CE
| | | | | |
PE PE PE PE PE PE
====|==========|=======|=======|=========|=====|======================
+-------+ | \ / / |
Bottom-up | | \ / / |
Network | | /\ / |
topology | | / \ | |
| | | | | |
node1 node2 node3 node4 node5 node6
Example of Layering relationships between L3VPN Service Topo and Underlying network
As shown in Figure 2, Site-1A, Site-1B, and Site-1C are mapped to nodes 1, 2, and 3, while Site-2A, Site-2B, and Site-2C are mapped to nodes 4, 5, and 6 in the underlying physical network. In this figure, a L3VPN Service Model (L3SM) [RFC8299] has two VPN services topologies with both built on top of one common underlying physical network.
L3VPN service topology 1 is hub and spoke topology while L3VPN service topology 2 is hub and spoke disjoint topology. In L3VPN service topology 1, Site-1 A plays the role of hub while Site-2 B and C plays the role of spoke. In L3VPN service topoogy 2, Site-2 A and B play the role of hub while Site-2 C plays the role of spoke.
An SP must be able to manage the capabilities and characteristics of their Network/VPN services when Network connection is established or VPN sites are setup to communicate with each other. Network and VPN service topology such as hub and spoke describes how these VPN sites are communicating with each other.
As described in section 2, once the mapping between overlay network topology/VPN Service topology and underlying physical network has been setup, the performance monitoring data per link in the underlying network can be collected using network performance measurement method such as MPLS Loss and Delay Measurement [RFC6374]. The performance monitoring information reflecting the quality of the Network or VPN service such as end to end network performance data between source node and destination node in the network or between VPN sites can be aggregated or calculated using PCEP solution [RFC5440] or LMAP solution [RFC8194]. The information can be fed into data source such as the management system or network devices. The measurement interval and report interval associated with these performance data usually depends on configuration parameters.
Some applications such as service-assurance applications, which must maintain a continuous view of operational data and state, can use subscription model [I-D.ietf-netconf-yang-push] to subscribe to the Network and VPN service performance data they are interested in, at the data source.
The data source can then use the Network and VPN service assurance model defined in this document and push model [I-D.ietf-netconf-yang-push] to publish specific telemetry data to target recipients.
To obtain a snapshot of a large amount of performance data from the network element, service-assurance applications can also use polling based solution such as RPC model to fetch performance data on demand.
This document defines the YANG module "ietf-network-vpn-svc-pm", which has the following structure
module: ietf-network-vpn-svc-pm
augment /nw:networks/nw:network/nw:network-types:
+--rw svc-topo-type? identityref
augment /nw:networks/nw:network:
+--rw svc-topo-attributes
+--rw vpn-topo? identityref
Network Level View of the hierarchies
For VPN service performance monitoring, this model defines only the following minimal set of Network level service topology attributes:
For network performance monitoring, the attributes of "Network Level" that defined in [RFC8345] do not need to be extended.
augment /nw:networks/nw:network/nw:node:
+--rw node-attributes
+--rw node-type? identityref
+--rw site-id? string
+--rw site-role? Identityref
Node Level View of the hierarchies
The Network and VPN service performance monitoring model defines only the following minimal set of Node level service topology attributes and constraints:
augment /nw:networks/nw:network/nt:link:
+--ro svc-telemetry-attributes
+--ro loss-statistics
| +--ro direction identityref
| +--ro packet-loss-count? uint32
| +--ro loss-ratio? percentage
| +--ro packet-reorder-count? uint32
| +--ro packets-out-of-seq-count? uint32
| +--ro packets-dup-count? uint32
+--ro delay-statistics
| +--ro direction? identityref
| +--ro min-delay-value? uint32
| +--ro max-delay-value? uint32
| +--ro average-delay-value? uint32
+--ro jitter-statistics
+--ro direction? identityref
+--ro min-jitter-value? uint32
+--ro max-jitter-value? uint32
+--ro average-jitter-value? uint32
augment /nw:networks/nw:network/nw:node/nt:termination-point:
+--ro tp-telemetry-attributes
+--ro in-octets? uint32
+--ro inbound-unicast? uint32
+--ro inbound-nunicast? uint32
+--ro inbound-discards? uint32
+--ro inbound-errors? uint32
+--ro inunknow-protos? uint32
+--ro out-octets? uint32
+--ro outbound-unicast? uint32
+--ro outbound-nunicast? uint32
+--ro outbound-discards? uint32
+--ro outbound-errors? uint32
+--ro outbound-qlen? uint32
Link and Termination point Level View of the hierarchies
The Network and VPN service performance monitoring model defines only the following minimal set of Link level service topology attributes:
The Network and VPN service performance monitoring defines the following minimal set of Termination point level service topology attributes:
This example shows the way for a client to subscribe for the Performance monitoring information between node A and node B in the L3 network topology built on top of the underlying optical network . The performance monitoring parameter that the client is interested in is end to end loss attribute.
<rpc netconf:message-id="101"
xmlns:netconf="urn:ietf:params:xml:ns:netconf:base:1.0">
<establish-subscription
xmlns="urn:ietf:params:xml:ns:yang:ietf-subscribed-notifications">
<stream-subtree-filter>
<networks xmlns="urn:ietf:params:xml:ns:yang:ietf-network-topo">
<network>
<network-id>l3-network</network-id>
<node>
<node-id>A</node-id>
<node-attributes xmlns="urn:ietf:params:xml:ns:yang:ietf-network-vpn-svc-pm">
<node-type>pe</node-type>
</node-attribtues>
<termination-point xmlns="urn:ietf:params:xml:ns:yang:ietf-network-topology">
<tp-id>1-0-1</tp-id>
<tp-telemetry-attributes xmlns="urn:ietf:params:xml:ns:yang:ietf-network-vpn-svc-pm">
<in-octets>100</in-octets>
<out-octets>150</out-octets>
</tp-telemetry-attributes>
</termination-point>
</node>
<node>
<node-id>B</node-id>
<node-attributes xmlns="urn:ietf:params:xml:ns:yang:ietf-network-vpn-svc-pm">
<node-type>pe</node-type>
</node-attribtues>
<termination-point xmlns="urn:ietf:params:xml:ns:yang:ietf-network-topology">
<tp-id>2-0-1</tp-id>
<tp-telemetry-attributes xmlns="urn:ietf:params:xml:ns:yang:ietf-network-vpn-svc-pm">
<in-octets>150</in-octets>
<out-octets>100</out-octets>
</tp-telemetry-attributes>
</termination-point>
</node>
<link xmlns="urn:ietf:params:xml:ns:yang:ietf-network-topology">
<link-id>A-B</link-id>
<source>
<source-node>A</source-node>
</source>
<destination>
<dest-node>B</dest-node>
</destination>
<svc-telemetry-attributes
xmlns="urn:ietf:params:xml:ns:yang:ietf-svc-topo">
<loss-statistics>
<packet-loss-count>100</packet-loss-count>
</loss-statistics>
</svc-telemetry-attributes>
</link>
</network>
</networks>
</stream-subtree-filter>
<period xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">500</period>
</establish-subscription>
</rpc>
This example shows the way for the client to use RPC model to fetch performance data on demand,e.g., the client requests packet-loss-count between PE1 in site 1 and PE2 in site 2 belonging to VPN1.
<rpc xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"
message-id="1">
<report xmlns="urn:ietf:params:xml:ns:yang:example-service-pm-report">
<networks xmlns="urn:ietf:params:xml:ns:yang:ietf-network-topo">
<network>
<network-id>vpn1</network-id>
<node>
<node-id>A</node-id>
<node-attributes xmlns="urn:ietf:params:xml:ns:yang:ietf-network-vpn-svc-pm">
<node-type>pe</node-type>
</node-attribtues>
<termination-point xmlns="urn:ietf:params:xml:ns:yang:ietf-network-topology">
<tp-id>1-0-1</tp-id>
<tp-telemetry-attributes xmlns="urn:ietf:params:xml:ns:yang:ietf-network-vpn-svc-pm">
<in-octets>100</in-octets>
<out-octets>150</out-octets>
</tp-telemetry-attributes>
</termination-point>
</node>
<node>
<node-id>B</node-id>
<node-attributes xmlns="urn:ietf:params:xml:ns:yang:ietf-network-vpn-svc-pm">
<node-type>pe</node-type>
</node-attribtues>
<termination-point xmlns="urn:ietf:params:xml:ns:yang:ietf-network-topology">
<tp-id>2-0-1</tp-id>
<tp-telemetry-attributes xmlns="urn:ietf:params:xml:ns:yang:ietf-network-vpn-svc-pm">
<in-octets>150</in-octets>
<out-octets>100</out-octets>
</tp-telemetry-attributes>
</termination-point>
</node>
<link-id>A-B</link-id>
<source>
<source-node>A</source-node>
</source>
<destination>
<dest-node>B</dest-node>
</destination>
<svc-telemetry-attributes xmlns="urn:ietf:params:xml:ns:yang:ietf-network-vpn-svc-pm">
<loss-statistics>
<packet-loss-count>120</packet-loss-count>
</loss-statistics>
</svc-telemetry-attributes>
</link>
</network>
</report>
</rpc>
<CODE BEGINS> file "ietf-network-vpn-svc-pm.yang"
module ietf-network-vpn-svc-pm {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-network-vpn-svc-pm";
prefix svc-topo;
import ietf-network {
prefix nw;
}
import ietf-network-topology {
prefix nt;
}
import ietf-l3vpn-svc {
prefix l3vpn-svc;
}
organization
"IETF xxx Working Group";
contact
"Zitao Wang: wangzitao@huawei.com
Qin Wu: bill.wu@huawei.com";
description
"This module defines a model for the VPN Service Performance monitoring.";
revision 2019-03-01 {
description
"Initial revision.";
reference
"foo";
}
identity service-type {
description
"Base type for service topology";
}
identity l3vpn-svc {
base service-type;
description
"Indentity for layer3 vpn service";
}
identity l2vpn-svc {
base service-type;
description
"Identity for layer2 vpn service";
}
identity node-type {
description
"Base identity for node type";
}
identity pe {
base node-type;
description
"Identity for PE type";
}
identity ce {
base node-type;
description
"Identity for CE type";
}
identity asbr {
base node-type;
description
"Identity for ASBR type";
}
identity p {
base node-type;
description
"Identity for P type";
}
identity direction {
description
"Base Identity for measurement direction including
one way measurement and two way measurement.";
}
identity oneway {
base direction;
description
"Identity for one way measurement.";
}
identity twoway {
base direction;
description
"Identity for two way measurement.";
}
typedef percentage {
type decimal64 {
fraction-digits 5;
range "0..100";
}
description
"Percentage.";
}
grouping link-error-statistics {
description
"Grouping for per link error statistics";
container loss-statistics {
description
"Per link loss statistics.";
leaf direction {
type identityref {
base direction;
}
default "oneway";
description
"Define measurement direction including one way
measurement and two way measurement.";
}
leaf packet-loss-count {
type uint32 {
range "0..4294967295";
}
default "0";
description
"Total received packet drops count.
The value of count will be set to zero (0)
on creation and will thereafter increase
monotonically until it reaches a maximum value
of 2^32-1 (4294967295 decimal), when it wraps
around and starts increasing again from zero.";
}
leaf loss-ratio {
type percentage;
description
"Loss ratio of the packets. Express as percentage
of packets lost with respect to packets sent.";
}
leaf packet-reorder-count {
type uint32 {
range "0..4294967295";
}
default "0";
description
"Total received packet reordered count.
The value of count will be set to zero (0)
on creation and will thereafter increase
monotonically until it reaches a maximum value
of 2^32-1 (4294967295 decimal), when it wraps
around and starts increasing again from zero.";
}
leaf packets-out-of-seq-count {
type uint32 {
range "0..4294967295";
}
description
"Total received out of sequence count.
The value of count will be set to zero (0)
on creation and will thereafter increase
monotonically until it reaches a maximum value
of 2^32-1 (4294967295 decimal), when it wraps
around and starts increasing again from zero..";
}
leaf packets-dup-count {
type uint32 {
range "0..4294967295";
}
description
"Total received packet duplicates count.
The value of count will be set to zero (0)
on creation and will thereafter increase
monotonically until it reaches a maximum value
of 2^32-1 (4294967295 decimal), when it wraps
around and starts increasing again from zero.";
}
}
}
grouping link-delay-statistics {
description
"Grouping for per link delay statistics";
container delay-statistics {
description
"Link delay summarised information. By default,
one way measurement protocol (e.g., OWAMP) is used
to measure delay.";
leaf direction {
type identityref {
base direction;
}
default "oneway";
description
"Define measurement direction including one way
measurement and two way measurement.";
}
leaf min-delay-value {
type uint32;
description
"Minimum delay value observed.";
}
leaf max-delay-value {
type uint32;
description
"Maximum delay value observed.";
}
leaf average-delay-value {
type uint32;
description
"Average delay is calculated on all the packets of a sample
and is a simple computation to be performed for single marking method.";
}
}
}
grouping link-jitter-statistics {
description
"Grouping for per link jitter statistics";
container jitter-statistics {
description
"Link jitter summarised information. By default,
jitter is measured using IP Packet Delay Variation
(IPDV) as defined in RFC3393.";
leaf direction {
type identityref {
base direction;
}
default "oneway";
description
"Define measurement direction including one way
measurement and two way measurement.";
}
leaf min-jitter-value {
type uint32;
description
"Minimum jitter value observed.";
}
leaf max-jitter-value {
type uint32;
description
"Maximum jitter value observed.";
}
leaf average-jitter-value {
type uint32;
description
"Average jitter is calculated on all the packets of a sample
and is a simple computation to be performed for single marking method.";
}
}
}
grouping tp-svc-telemetry {
leaf in-octets {
type uint32;
description
"The total number of octets received on the
interface, including framing characters.";
}
leaf inbound-unicast {
type uint32;
description
"Inbound unicast packets were received, and delivered
to a higher layer during the last period.";
}
leaf inbound-nunicast {
type uint32;
description
"The number of non-unicast (i.e., subnetwork-
broadcast or subnetwork-multicast) packets
delivered to a higher-layer protocol.";
}
leaf inbound-discards {
type uint32;
description
"The number of inbound packets which were chosen
to be discarded even though no errors had been
detected to prevent their being deliverable to a
higher-layer protocol.";
}
leaf inbound-errors {
type uint32;
description
"The number of inbound packets that contained
errors preventing them from being deliverable to a
higher-layer protocol.";
}
leaf inunknow-protos {
type uint32;
description
"The number of packets received via the interface
which were discarded because of an unknown or
unsupported protocol";
}
leaf out-octets {
type uint32;
description
"The total number of octets transmitted out of the
interface, including framing characters";
}
leaf outbound-unicast {
type uint32;
description
"The total number of packets that higher-level
protocols requested be transmitted to a
subnetwork-unicast address, including those that
were discarded or not sent.";
}
leaf outbound-nunicast {
type uint32;
description
"The total number of packets that higher-level
protocols requested be transmitted to a non-
unicast (i.e., a subnetwork-broadcast or
subnetwork-multicast) address, including those
that were discarded or not sent.";
}
leaf outbound-discards {
type uint32;
description
"The number of outbound packets which were chosen
to be discarded even though no errors had been
detected to prevent their being transmitted. One
possible reason for discarding such a packet could
be to free up buffer space.";
}
leaf outbound-errors {
type uint32;
description
"The number of outbound packets that contained
errors preventing them from being deliverable to a
higher-layer protocol.";
}
leaf outbound-qlen {
type uint32;
description
" Length of the queue of the interface from where
the packet is forwarded out. The queue depth could
be the current number of memory buffers used by the
queue and a packet can consume one or more memory buffers
thus constituting device-level information.";
}
description
"Grouping for interface service telemetry";
}
augment "/nw:networks/nw:network/nw:network-types" {
description
"Augment the network-types with service topologyies types";
leaf svc-topo-type {
type identityref {
base service-type;
}
description
"Identify the topology type to be composited service topology";
}
}
augment "/nw:networks/nw:network" {
description
"Augment the network with service topology attributes";
container svc-topo-attributes {
leaf vpn-topology {
type identityref {
base l3vpn-svc:vpn-topology;
}
description
"VPN service topology, e.g. hub-spoke, any-to-any, hub-spoke-disjoint, etc";
}
description
"Container for vpn services";
}
}
augment "/nw:networks/nw:network/nw:node" {
description
"Augment the network node with serice attributes";
container node-attributes {
leaf node-type {
type identityref {
base node-type;
}
description
"Node type, e.g. PE, P, ASBR, etc";
}
leaf site-id {
type string;
description
"Asscoiated vpn site";
}
leaf site-role {
type identityref {
base l3vpn-svc:site-role;
}
default "l3vpn-svc:any-to-any-role";
description
"Role of the site in the IP VPN.";
}
description
"Container for service topology attributes";
}
}
augment "/nw:networks/nw:network/nt:link" {
description
"Augment the network topology link with vpn service attributes";
container svc-telemetry-attributes {
config false;
uses link-error-statistics;
uses link-delay-statistics;
uses link-jitter-statistics;
description
"Container for service telemetry attributes";
}
}
augment "/nw:networks/nw:network/nw:node/nt:termination-point" {
description
"Augment the network topology termination point with vpn service attributes";
container tp-telemetry-attributes {
config false;
uses tp-svc-telemetry;
description
"Container for termination point service telemetry attributes.";
}
}
}
<CODE ENDS>
The YANG modules defined in this document MAY be accessed via the RESTCONF protocol [RFC8040] or NETCONF protocol ([RFC6241]). The lowest RESTCONF or NETCONF layer requires that the transport-layer protocol provides both data integrity and confidentiality, see Section 2 in [RFC8040] and [RFC6241]. The lowest NETCONF layer is the secure transport layer, and the mandatory-to-implement secure transport is Secure Shell (SSH)[RFC6242] . The lowest RESTCONF layer is HTTPS, and the mandatory-to-implement secure transport is TLS [RFC5246].
The NETCONF access control model [RFC6536] provides the means to restrict access for particular NETCONF or RESTCONF users to a preconfigured subset of all available NETCONF or RESTCONF protocol operations and content.
There are a number of data nodes defined in this YANG module that are writable/creatable/deletable (i.e., config true, which is the default). These data nodes may be considered sensitive or vulnerable in some network environments. Write operations (e.g., edit-config) to these data nodes without proper protection can have a negative effect on network operations. These are the subtrees and data nodes and their sensitivity/vulnerability:
This document registers a URI in the IETF XML registry [RFC3688]. Following the format in [RFC3688], the following registration is requested to be made:
--------------------------------------------------------------------- URI: urn:ietf:params:xml:ns:yang:ietf-network-vpn-svc-pm Registrant Contact: The IESG. XML: N/A, the requested URI is an XML namespace. ---------------------------------------------------------------------
This document registers a YANG module in the YANG Module Names registry [RFC6020].
--------------------------------------------------------------------- Name: ietf-vpn-svc-pm Namespace: urn:ietf:params:xml:ns:yang:ietf-network-vpn-svc-pm Prefix: vnrsc Reference: RFC xxxx ---------------------------------------------------------------------