Internet DRAFT - draft-wd-teas-ietf-network-slice-nbi-yang
draft-wd-teas-ietf-network-slice-nbi-yang
Network Working Group B. Wu
Internet-Draft D. Dhody
Intended status: Standards Track Huawei Technologies
Expires: 30 March 2022 R. Rokui
Nokia
T. Saad
Juniper Networks
L. Han
China Mobile
L.M. Contreras
Telefonica
26 September 2021
IETF Network Slice Service YANG Model
draft-wd-teas-ietf-network-slice-nbi-yang-05
Abstract
This document provides a YANG data model for the IETF Network Slice
service. The model can be used by a IETF Network Slice Customer to
manage IETF Network Slice from an IETF Network Slice Controller
(NSC).
Status of This Memo
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 30 March 2022.
Copyright Notice
Copyright (c) 2021 IETF Trust and the persons identified as the
document authors. All rights reserved.
Wu, et al. Expires 30 March 2022 [Page 1]
Internet-Draft IETF Network Slice NBI YANG model September 2021
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.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions used in this document . . . . . . . . . . . . . . 3
2.1. Tree Diagrams . . . . . . . . . . . . . . . . . . . . . . 4
3. IETF Network Slice Service Model Usage . . . . . . . . . . . 4
4. Background on IETF Network Slice Service Modeling . . . . . . 5
4.1. LxSM VPN Service Models . . . . . . . . . . . . . . . . . 5
4.2. ACTN VN Model Augmentation analysis . . . . . . . . . . . 5
5. IETF Network Slice Service Model Overview . . . . . . . . . . 8
6. IETF Network Slice Templates . . . . . . . . . . . . . . . . 12
7. IETF Network Slice Modeling Description . . . . . . . . . . . 12
7.1. IETF Network Slice Connectivity Type . . . . . . . . . . 13
7.2. IETF Network Slice SLO and SLE Policy . . . . . . . . . . 14
7.3. IETF Network Slice Endpoint (NSE) . . . . . . . . . . . . 16
8. IETF Network Slice Monitoring . . . . . . . . . . . . . . . . 19
9. IETF Network Slice Service Module . . . . . . . . . . . . . . 20
10. Security Considerations . . . . . . . . . . . . . . . . . . . 40
11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 41
12. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 41
13. References . . . . . . . . . . . . . . . . . . . . . . . . . 41
13.1. Normative References . . . . . . . . . . . . . . . . . . 41
13.2. Informative References . . . . . . . . . . . . . . . . . 43
Appendix A. IETF Network Slice NBI Model Usage Example . . . . . 44
Appendix B. Appendix B IETF Network Slice Match Criteria . . . . 47
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 48
1. Introduction
This document provides a YANG [RFC7950] data model for the IETF
Network Slice service.
The YANG model discussed in this document is defined based on the
description of the IETF Network Slice in
[I-D.ietf-teas-ietf-network-slices], which is used to operate IETF
Network Slices during the IETF Network Slice instantiation. This
YANG model supports various operations on IETF Network Slices such as
creation, modification, deletion, and monitoring.
Wu, et al. Expires 30 March 2022 [Page 2]
Internet-Draft IETF Network Slice NBI YANG model September 2021
The IETF Network Slice Controller (NSC) is a logical entity that
allows customers to manage IETF network slices. Details related to
the realization of IETF network slices that fulfil the request are
internal to the entity that operates the network. Such details are
deployment- and implementation-specific.
The NSC receives request from its customer-facing interface (e.g.,
from a management system). This interface carries data objects the
IETF network slice user provides, describing the needed IETF network
slices in terms of topology, target service level objectives (SLO),
and also monitoring and reporting requirements. These requirements
are then translated into technology-specific actions that are
implemented in the underlying network using a network-facing
interface. The details of IETF network slices realization are out of
scope for this document.
The YANG model discussed in this document describes the requirements
of an IETF Network Slice from the point of view of the customer. It
is thus classified as customer service model in [RFC8309].
The IETF Network Slice operational state is included in the same tree
as the configuration consistent with Network Management Datastore
Architecture [RFC8342].
2. Conventions used in this document
The keywords "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
BCP14, [RFC2119], [RFC8174] when, and only when, they appear in all
capitals, as shown here.
The following terms are defined in [RFC6241] and are used in this
specification:
* client
* configuration data
* state data
This document makes use of the terms defined in [RFC7950].
This document also makes use of the terms introduced in the Framework
for IETF Network Slices [I-D.ietf-teas-ietf-network-slices]:
This document defines the following term:
Wu, et al. Expires 30 March 2022 [Page 3]
Internet-Draft IETF Network Slice NBI YANG model September 2021
* IETF Network Slice Connection (NS-Connection): In the context of
an IETF Network Slice, an IETF NS-Connection is an abstract entity
which represents a particular connection between a pair of NSEs.
An IETF Network Slice can has one or multiple NS-Connections.
2.1. Tree Diagrams
The tree diagram used in this document follow the notation defined in
[RFC8340].
3. IETF Network Slice Service Model Usage
The intention of the IETF Network Slice service model is to allow the
customer to manage IETF Network Slices. In particular, the model
allows customers to operate in an abstract and technology-agnostic
manner, with details of the IETF Network Slices realization hidden.
According to the [I-D.ietf-teas-ietf-network-slices] description,
IETF Network Slices are applicable to use cases such as (but not
limited to) network wholesale services, network infrastructure
sharing among operators, NFV connectivity, Data Center Interconnect,
and 5G E2E network slice.
As shown in Figure 1, in all these use-cases, the model is used by
the higher management system to communicate with NSC for life cycle
manage of IETF Network Slices including both enablement and
monitoring. The interface is used to support dynamic IETF Network
Slice creation and its lifecycle management to facilitate end-to-end
network slice services.
+----------------------------------------+
| IETF Network Slice Customer |
| |
+----------------+-----------------------+
|
|
|IETF Network Slice service model YANG
|
+---------------------+--------------------------+
| IETF Network Slice Controller (NSC) |
+------------------------------------------------+
Figure 1: IETF Network Slice Service Reference Architecture
Wu, et al. Expires 30 March 2022 [Page 4]
Internet-Draft IETF Network Slice NBI YANG model September 2021
4. Background on IETF Network Slice Service Modeling
[I-D.ietf-teas-ietf-network-slices] defines the IETF Network Slice
service model as a technology agnostic interface. That is, customer
expresses requirements for a particular slice by specifying what is
required rather than how that is to be achieved.
This section explains why a new YANG service data model is proposed
for support of IETF network slice services. The following data
models are considered:
* L3SM, L2SM and L1CSM models
* ACTN VN model
4.1. LxSM VPN Service Models
Currently, the three VPN service models defined at IETF are L3SM
[RFC8299], L2SM [RFC8466], L1CSM [I-D.ietf-ccamp-l1csm-yang]. These
models are related to specific VPN technologies. When using these
models as a slicing service interface, customers need to be aware of
the network's VPN technology so that right interfaces can be used.
The IETF network slice service requires a technology agnostic
interface (similar to intent), to avoiding using multiple VPN models
or other technology specific models.
4.2. ACTN VN Model Augmentation analysis
Abstraction and Control of TE Networks (ACTN - [RFC8453]) defines a
virtual network (VN) service [I-D.ietf-teas-actn-vn-yang]. Figure 2
shows that the relationship of IETF network slice and ACTN framework.
ACTN VN is independent of VPN technologies, and relys on traffic
engineering YANG model [RFC8795] to define VN service in terms of a
topology with a single abstract node and its connectivity matrix.
Wu, et al. Expires 30 March 2022 [Page 5]
Internet-Draft IETF Network Slice NBI YANG model September 2021
IETF Network Slice | ACTN analogous
Terminology / Concepts Terminology
| and Concepts
+--------------------------------------+
|Consumer higher level operation system| | +-----+
| (e.g E2E network slice orchestrator) | =====> | CNC |
+--------------------------------------+ | +-----+
^ ^
| NSC NBI | | CMI
v v
+-------------------------------------+ | +------+
| IETF Network Slice Controller (NSC) | =====> | MDSC |
+-------------------------------------+ | +------+
^ ^
| NSC SBI | | MPI
v v
+-------------------------------------+ | +-----+
| Network Controller(s) | =====> | PNC |
+-------------------------------------+ | +-----+
Figure 2: ACTN mapping
The ACTN VN model introduced in[I-D.ietf-teas-actn-vn-yang] is an
abstract customer view of the TE network. Its YANG structure
includes four components:
* VN: A Virtual Network (VN) is a network provided by a service
provider to a customer for use and two types of VN has defined.
The Type 1 VN can be seen as a set of edge-to-edge abstract links
between VNAP.
* AP: An AP is a logical identifier used to identify the access link
which is shared between the customer and the IETF scoped Network.
* VN-AP: A VN-AP is a logical binding between an AP and a given VN.
* VN-member: A VN-member is an abstract edge-to-edge link between
any two APs or VN-APs.
Figure 3 illustrates the difference between AP/VNAPs in a VN and NSEs
of IETF network slice. Though AP is a logical identifier, it maps to
a access link between the customer nodes and provider nodes, which is
also TP (Termination Port) of the provider node). When the access
link changes, the VN connection matrix changes accordingly. For
example, when the backup link of AP5/TP5 is added, the corresponding
VN members, AP5-AP3 and AP5-AP4, also need to be added. These
changes are underlying topology details. The slice service focuses
on the connection matrix between C1, C2, and C3.
Wu, et al. Expires 30 March 2022 [Page 6]
Internet-Draft IETF Network Slice NBI YANG model September 2021
+----------------------+
| TE topology 1 | +------------+
+---+ | +---+ +---+ | TP1 | | TP3
|C2 +-+----|P1 | |P3 |TP3 | ----| |----
+---+\| TP1+---+\ /+---+\ | \ TP2 | | TP4
\ \/ \ | ---\ ----| AN1 |----
| \TP5 /\ \| / TP3 | |
+---+ | \+---+/ \+---+ \ +---+ ----| |
|C1 +-+----|P2 |----|P4 |-----\+ C3| +------------+
+---+ | TP2+---+ +---+TP4 | +---+ Abstract Node
+----------------------+ TE topology
\|/
+---------------+
AP1 ------| |------ AP3
AP2 ------| |------ AP4 +------------+
AP5 ------| VN 1 | | |
| | | |
+---------------+ NSE1 O |
VN-Member 1 AP1-AP3 | O NSE3
VN-Member 2 AP1-AP4 NSE2 O |
VN-Member 3 AP2-AP3 | |
VN-Member 4 AP2-AP4 +------------+
VN-Member 5 AP5-AP3 Network slice 1
VN-Member 6 AP5-AP4
Legend:
TP:Termination Point
AP:Access Point
Figure 3: Difference between AP and NSE
In summary, the ACTN VN model cannot be used to model the IETF
network slice service model because the VN model is tightly bound to
the IETF TE Topology model and the constraints are buried deep inside
the TE topology connectivity matrix and thus does not provide a clear
mechanism to specify SLO/SLE of IETF network slice. The IETF network
slice endpoint also does not ascribe to the concept of AP/VNAP. The
realization of the IETF Network Slice does not necessarily require
the slice network to support the TE technology. As the IETF network
slice could be realized with non-TE techniques (FlexAlgo, MT).
Reusing or augmenting VN model is problematic.
Wu, et al. Expires 30 March 2022 [Page 7]
Internet-Draft IETF Network Slice NBI YANG model September 2021
5. IETF Network Slice Service Model Overview
As defined in [I-D.ietf-teas-ietf-network-slices], an IETF Network
Slice is a logical network topology connecting a number of endpoints
using a set of shared or dedicated network resources that are used to
satisfy specific service requirements. The logical topology types
are: point-to-point, point-to-multipoint, multipoint-to-point, or
multipoint-to-multipoint. The endpoints are conceptual points that
could map to a device, application or a network function. And the
specific service requirements, typically expressed as bandwidth,
latency, latency variation, and other desired or required
characteristics, such as security, MTU, traffic-type (e.g., IPv4,
IPv6, Ethernet or unstructured) or a higher-level behavior to process
traffic according to user-application (which may be realized using
network function). An example of an IETF network slice is shown in
Figure 4 .
+----------------------------------------------+
| |
NSE1 O------------------+ |
. +---------------------------O NSE2
. | .
. | multipoint-to-multipoint .
. | .
. +---------------------------O NSEn
NSEm O------------------+ |
| |
+----------------------------------------------+
| |
|<-----------An IETF Network Slice ---------->|
| between endpoints NSE1 to NSEn |
Legend:
NSE: IETF Network Slice Endpoint
O: Represents IETF Network Slice Endpoints
Figure 4: An IETF Network Slice Example
As shown in the example, an IETF network slice may have multiple
NSEs. The NSEs are the ingress/egress points where traffic enters/
exits the IETF network slice. As the edge of the IETF network slice,
the NSEs also delimit a topological network portion within which the
committed SLOs apply.
When an NSC receives a message via its customer-facing interface for
creation/modification of an IETF network slice, it uses the provided
NSEs to retrieve the corresponding border link or "Provider Node"
Wu, et al. Expires 30 March 2022 [Page 8]
Internet-Draft IETF Network Slice NBI YANG model September 2021
(e.g., PE). The NSC further maps them to the appropriate
service/tunnel/path endpoints in the underlying network. It then
uses services/tunnels/paths to realize the IETF network slice.
The 'ietf-network-slice' module uses two main data nodes: list 'ietf-
network-slice' and container 'ns-templates' (see Figure 5).
The 'ietf-network-slice' list includes the set of IETF Network slices
managed within a provider network. 'ietf-network-slice' is the data
structure that abstracts an IETF Network Slice. Under the "ietf-
network-slice", list "ns-endpoint" is used to abstract the NSEs, e.g.
NSEs in the example above. And list "ns-connection" is used to
abstract connections between NSEs.
The 'ns-templates' container is used by the NSC to maintain a set of
common network slice templates that apply to one or several IETF
Network Slices.
The figure below describes the overall structure of the YANG module:
module: ietf-network-slice
+--rw network-slices
+--rw ns-slo-sle-templates
| +--rw ns-slo-sle-template* [id]
| +--rw id string
| +--rw template-description? string
+--rw network-slice* [ns-id]
+--rw ns-id string
+--rw ns-description? string
+--rw customer-name* string
+--rw ns-connectivity-type? identityref
+--rw (ns-slo-sle-policy)?
| +--:(standard)
| | +--rw slo-sle-template? leafref
| +--:(custom)
| +--rw slo-sle-policy
| +--rw policy-description? string
| +--rw ns-metric-bounds
| | +--rw ns-metric-bound* [metric-type]
| | +--rw metric-type identityref
| | +--rw metric-unit string
| | +--rw value-description? string
| | +--rw bound? uint64
| +--rw security* identityref
| +--rw isolation? identityref
| +--rw max-occupancy-level? uint8
| +--rw mtu uint16
| +--rw steering-constraints
Wu, et al. Expires 30 March 2022 [Page 9]
Internet-Draft IETF Network Slice NBI YANG model September 2021
| +--rw path-constraints
| +--rw service-function
+--rw status
| +--rw admin-enabled? boolean
| +--ro oper-status? operational-type
+--rw ns-endpoints
| +--rw ns-endpoint* [ep-id]
| +--rw ep-id string
| +--rw ep-description? string
| +--rw ep-role? identityref
| +--rw location
| | +--rw altitude? int64
| | +--rw latitude? decimal64
| | +--rw longitude? decimal64
| +--rw node-id? string
| +--rw ep-ip? inet:host
| +--rw ns-match-criteria
| | +--rw ns-match-criterion* [match-type]
| | +--rw match-type identityref
| | +--rw values* [index]
| | +--rw index uint8
| | +--rw value? string
| +--rw ep-peering
| | +--rw protocol* [protocol-type]
| | +--rw protocol-type identityref
| | +--rw attribute* [index]
| | +--rw index uint8
| | +--rw attribute-description? string
| | +--rw value? string
| +--rw ep-network-access-points
| | +--rw ep-network-access-point* [network-access-id]
| | +--rw network-access-id string
| | +--rw network-access-description? string
| | +--rw network-access-node-id? string
| | +--rw network-access-tp-id? string
| | +--rw network-access-tp-ip? inet:host
| | +--rw mtu uint16
| | +--rw ep-rate-limit
| | +--rw incoming-rate-limit?
| | | te-types:te-bandwidth
| | +--rw outgoing-rate-limit?
| | te-types:te-bandwidth
| +--rw ep-rate-limit
| | +--rw incoming-rate-limit? te-types:te-bandwidth
| | +--rw outgoing-rate-limit? te-types:te-bandwidth
| +--rw status
| | +--rw admin-enabled? boolean
| | +--ro oper-status? operational-type
Wu, et al. Expires 30 March 2022 [Page 10]
Internet-Draft IETF Network Slice NBI YANG model September 2021
| +--ro ep-monitoring
| +--ro incoming-utilized-bandwidth?
| | te-types:te-bandwidth
| +--ro incoming-bw-utilization decimal64
| +--ro outgoing-utilized-bandwidth?
| | te-types:te-bandwidth
| +--ro outgoing-bw-utilization decimal64
+--rw ns-connections
+--rw ns-connection* [ns-connection-id]
+--rw ns-connection-id uint32
+--rw ns-connection-description? string
+--rw src
| +--rw src-ep-id? leafref
+--rw dest
| +--rw dest-ep-id? leafref
+--rw (ns-slo-sle-policy)?
| +--:(standard)
| | +--rw slo-sle-template? leafref
| +--:(custom)
| +--rw slo-sle-policy
| +--rw policy-description? string
| +--rw ns-metric-bounds
| | +--rw ns-metric-bound* [metric-type]
| | +--rw metric-type identityref
| | +--rw metric-unit string
| | +--rw value-description? string
| | +--rw bound? uint64
| +--rw security* identityref
| +--rw isolation? identityref
| +--rw max-occupancy-level? uint8
| +--rw mtu uint16
| +--rw steering-constraints
| +--rw path-constraints
| +--rw service-function
+--rw monitoring-type? ns-monitoring-type
+--ro ns-connection-monitoring
+--ro latency? yang:gauge64
+--ro jitter? yang:gauge32
+--ro loss-ratio? decimal64
Figure 5
Wu, et al. Expires 30 March 2022 [Page 11]
Internet-Draft IETF Network Slice NBI YANG model September 2021
6. IETF Network Slice Templates
The 'ns-templates' container (Figure 5) is used by service provider
of the NSC to define and maintain a set of common IETF Network Slice
templates that apply to one or several IETF Network Slices. The
exact definition of the templates is deployment specific to each
network provider.
The model includes only the identifiers of SLO and SLE templates.
When creation of IETF Network slice, the SLO and SLE policies can be
easily identified.
The following shows an example where two network slice templates can
be retrieved by the upper layer management system:
{
"ietf-network-slices": {
"ns-templates": {
"slo-sle-template": [
{
"id":"GOLD-template",
"template-description": "Two-way bandwidth: 1 Gbps,
one-way latency 100ms "
"sle-isolation":"ns-isolation-shared",
},
{
"id":"PLATINUM-template",
"template-description": "Two-way bandwidth: 1 Gbps,
one-way latency 50ms "
"sle-isolation":"ns-isolation-dedicated",
},
],
}
}
}
7. IETF Network Slice Modeling Description
The 'ietf-network-slice' is the data structure that abstracts an IETF
Network Slice of the IETF network. Each 'ietf-network-slice' is
uniquely identified by an identifier: 'ns-id'.
An IETF Network Slice has the following main parameters:
* "ns-id": Is an identifier that is used to uniquely identify the
IETF Network Slice within NSC.
Wu, et al. Expires 30 March 2022 [Page 12]
Internet-Draft IETF Network Slice NBI YANG model September 2021
* "ns-description": Gives some description of an IETF Network Slice
service.
* "ns-connectivity-type": Indicates the network connectivity type
for the IETF Network Slice: Hub-and-Spoke, any-to-any, or custom
type.
* "status": Is used to show the operative and administrative status
of the IETF Network Slice, and can be used as indicator to detect
network slice anomalies.
* "customer-name": Is used to show the correlation between actual
slice customers and IETF network slices. It can be used by the
NSC for monitoring and assurance of the IETF network slices where
NSC can notify the higher system by issuing the notifications.
For example, multiple actual customers use a same network slice.
* "ns-slo-sle-policy": Defines SLO and SLE policies for the "ietf-
network-slice". More description are provided in Section 7.2
The "ns-endpoint" is an abstrac entity that represents a set of
matching rules applied to an IETF network edge device or a customer
network edge device involved in the IETF Network Slice and each 'ns-
endpoint' belongs to a single 'ietf-network-slice'. More description
are provided in Section 7.3
7.1. IETF Network Slice Connectivity Type
Based on the customer's traffic pattern requirements, an IETF Network
Slice connection type could be point-to-point (P2P), point-to-
multipoint (P2MP), multipoint-to-point (MP2P), or multipoint-to-
multipoint (MP2MP). The "ns-connectivity-type" under the node "ietf-
network-slice" is used for this.
According to the network services defined in
[I-D.ietf-opsawg-vpn-common], some well-known connectivity types are
proposed for IETF network slices. The type could be any-to-any, Hub-
and-Spoke (where Hubs can exchange traffic), and the custom. By
default, the any-to-any is used. New connectivity type could be
added via augmentation or by list of 'ns-connection' specified.
In addition, "ep-role" under the node "ns-endpoint" also needs to be
defined, which specifies the role of the NSE in a particular Network
Slice connectivity type. In the any-to-any, all NSEs MUST have the
same role, which will be "any-to-any-role". In the Hub-and-Spoke,
NSEs MUST have a Hub role or a Spoke role.
Wu, et al. Expires 30 March 2022 [Page 13]
Internet-Draft IETF Network Slice NBI YANG model September 2021
7.2. IETF Network Slice SLO and SLE Policy
As defined in [I-D.ietf-teas-ietf-network-slices], the SLO and SLE
policy of an IETF Network Slice defines the minimum IETF Network
Slice SLO attributes, and additional attributes can be added as
needed.
"ns-slo-sle-policy" is used to represent specific SLO and SLE
policies. During the creation of an IETF Network Slice, the policy
can be specified either by a standard SLO and SLO template or a
customized SLO and SLE policy.
The policy could both apply one per Network Slice or per connection
'ns-connection'.
The model allows multiple SLO and SLE attributes to be combined to
meet different SLO and SLE requirements. For example, some NSs are
used for video services and require high bandwidth, some NSs are used
for key business services and request low latency and reliability,
and some NSs need to provide connections for a large number of NSEs.
That is, not all SLO or SLE attributes must be specified to meet the
particular requirements of a slice.
"ns-metric-bounds" contains all these variations, which includes a
list of "ns-metric-bound" and each "ns-metric-bound" could specify a
particular "metric-type". "metric-type" is defined with YANG identity
and the YANG module supports the following options:
"ns-slo-one-way-bandwidth": Indicates the guaranteed minimum
bandwidth between any two NSE. And the bandwidth is
unidirectional.
"ns-slo-two-way-bandwidth": Indicates the guaranteed minimum
bandwidth between any two NSE. And the bandwidth is
bidirectional.
"network-slice-slo-one-way-latency": Indicates the maximum one-way
latency between two NSE.
"network-slice-slo-two-way-latency": Indicates the maximum round-
trip latency between two NSE.
"ns-slo-one-way-delay-variation": Indicates the jitter constraint
of the slice maximum permissible delay variation, and is measured
by the difference in the one-way latency between sequential
packets in a flow.
"ns-slo-two-way-delay-variation": Indicates the jitter constraint
Wu, et al. Expires 30 March 2022 [Page 14]
Internet-Draft IETF Network Slice NBI YANG model September 2021
of the slice maximum permissible delay variation, and is measured
by the difference in the two-way latency between sequential
packets in a flow.
"ns-slo-one-way-packet-loss": Indicates maximum permissible packet
loss rate, which is defined by the ratio of packets dropped to
packets transmitted between two endpoints.
"ns-slo-two-way-packet-loss": Indicates maximum permissible packet
loss rate, which is defined by the ratio of packets dropped to
packets transmitted between two endpoints.
"ns-slo-availability": Is defined as the ratio of up-time to
total_time(up-time+down-time), where up-time is the time the IETF
Network Slice is available in accordance with the SLOs associated
with it.
Some other Network Slice SLOs or SLEs could be extended when needed.
Note: The definition of "slo-sle-policy" and "steering-constraints"
will be updated when WG converge on the terms.
Note: RFC7297 shaping/policing for out of profile traffic.
The following shows an example where a network slice policy can be
configured:
Wu, et al. Expires 30 March 2022 [Page 15]
Internet-Draft IETF Network Slice NBI YANG model September 2021
{
"ietf-network-slices": {
"ietf-network-slice": {
"slo-policy": {
"policy-description":"video-service-policy",
"ns-metric-bounds": {
"ns-metric-bound": [
{
"metric-type": "ns-slo-one-way-bandwidth",
"metric-unit": "mbps"
"bound": "1000"
},
{
"metric-type": "ns-slo-availability",
"bound": "99.9%"
},
],
}
}
}
}
}
7.3. IETF Network Slice Endpoint (NSE)
An IETF Network Slice Endpoint has several characteristics:
* "ep-id": Uniquely identifies the NSE within Network Slice
Controller (NSC). The identifier is a string that allows any
encoding for the local administration of the IETF Network Slice.
* "location": Indicates NSE location information that facilities NSC
easy identification of a NSE.
* "ep-role": Represents a connectivity type role of a NSE belonging
to an IETF network slice, as described in Section 7.1. The "ep-
role" leaf defines the role of the endpoint in a particular NS
connectivity type. In the any-to-any, all NSEs MUST have the same
role, which will be "any-to-any-role".
* "node-id": The NSE node information facilities NSC with easy
identification of a NSE.
* "ep-ip": The NSE IP information facilities NSC with easy
identification of a NSE.
* "ns-match-criteria": A matching policies to apply on a given NSE.
Wu, et al. Expires 30 March 2022 [Page 16]
Internet-Draft IETF Network Slice NBI YANG model September 2021
* "ep-network-access-points": The list of the interfaces attached to
an edge device of the IETF Network Slice by which the customer
traffic is received.
* "ep-rate-limit": Set the rate-limiting policies to apply on a
given NSE, including ingress and egress traffic to ensure access
security. When applied in the incoming direction, the rate-limit
is applicable to the traffic from the NSE to the IETF scope
Network that passes through the external interface. When
Bandwidth is applied to the outgoing direction, it is applied to
the traffic from the IETF Network to the NSE of that particular
NS.
* "ep-protocol": Specify the protocol for a NSE for exchanging
control-plane information, e.g. L1 signaling protocol or L3
routing protocols,etc.
* "status": Enable the control of the operative and administrative
status of the NSE, can be used as indicator to detect NSE
anomalies.
An NSE belong to a single IETF Network Slice. An IETF Network Slice
involves two or more NSEs. An IETF Network Slice can be modified by
adding new "ns-endpoint" or removing existing "ns-endpoint".
A NSE is used to define the matching rule on the customer traffic
that can be injected to an IETF Network Slice. "network-slice-match-
criteria" is defined to support different options. Classification
can be based on many criteria, such as:
* Physical interface: Indicates all the traffic received from the
interface belongs to the IETF Network Slice.
* Logical interface: For example, a given VLAN ID is used to
identify an IETF Network Slice.
* Encapsulation in the traffic header: For example, a source IP
address is used to identify an IETF Network Slice.
To illustrate the use of NSE parameters, the below are two examples.
How the NSC realize the mapping is out of scope for this document.
Wu, et al. Expires 30 March 2022 [Page 17]
Internet-Draft IETF Network Slice NBI YANG model September 2021
* NSE with PE parameters example: As shown in Figure 6 , customer of
the IETF network slice would like to connect two NSEs to satisfy
specific service, e.g., Network wholesale services. In this case,
the IETF network slice endpoints are mapped to physical interfaces
of PE nodes. The IETF network slice controller (NSC) uses 'node-
id' (PE device ID), 'ep-network-access-points' (Two PE interfaces
) to map the interfaces and corresponding services/tunnels/paths.
NSE1 NSE2
(With PE1 parameters) (with PE2 parameters)
o<--------- IETF Network Slice 1 ------->o
+ | | +
+ |<----------- S1 ----------->| +
+ | | +
+ | |<------ T1 ------>| | +
+ v v v v +
+ +----+ +----+ +
+-----+ | | PE1|==================| PE2| +-----+
| |----------X | | | | | |
| | | | | | X----------| |
| |----------X | | | | | |
+-----+ | | |==================| | | +-----+
AC +----+ +----+ AC
Customer Provider Provider Customer
Edge 1 Edge 1 Edge 2 Edge 2
Legend:
O: Representation of the IETF network slice endpoints (NSE)
+: Mapping of NES to PE or CE nodes on IETF network
X: Physical interfaces used for realization of IETF network slice
S1: L0/L1/L2/L3 services used for realization of IETF network slice
T1: Tunnels used for realization of IETF network slice
Figure 6
* NSE with CE parameters example: As shown in Figure 7 , customer of
the IETF network slice would like to connect two NSEs to provide
connectivity between transport portion of 5G RAN to 5G Core
network functions. In this scenario, the IETF network slice
controller (NSC) uses 'node-id' (CE device ID) , 'ep-ip' (CE
tunnel endpoint IP), 'network-slice-match-criteria' (VLAN
interface), 'ep-network-access-points' (Two nexthop interfaces )
to retrieve the corresponding border link or PE, and further map
to services/tunnels/paths.
Wu, et al. Expires 30 March 2022 [Page 18]
Internet-Draft IETF Network Slice NBI YANG model September 2021
NSE3 NSE4
(With CE1 parameters) (with CE2 parameters)
o<--------- IETF Network Slice 2 ------->o
+ | | +
+ |<----------- S2 ----------->| +
+ | | +
+ | |<------ T2 ------>| | +
+ v v v v +
+ +----+ +----+ +
+-----+ | + | PE1|==================| PE2| + | +-----+
| |----------X | | | | | |
| | | | | | X----------| |
| |----------X | | | | | |
+-----+ | | |==================| | | +-----+
AC +----+ +----+ AC
Customer Provider Provider Customer
Edge 1 Edge 1 Edge 2 Edge 2
Legend:
O: Representation of the IETF network slice endpoints (NSE)
+: Mapping of NSE to PE or CE-PE interfaces on IETF network
X: Physical interfaces used for realization of IETF network slice
S2: L0/L1/L2/L3 services used for realization of IETF network slice
T2: Tunnels used for realization of IETF network slice
Figure 7
Note: The model needs to be optimized for better extension of other
protocols or AC technologies.
8. IETF Network Slice Monitoring
An IETF Network Slice is a connectivity with specific SLO
characteristics, including bandwidth, latency, etc. The connectivity
is a combination of logical unidirectional connections, represented
by 'ns-connection'.
This model also describes performance status of an IETF Network
Slice. The statistics are described in the following granularity:
* Per NS connection: specified in 'ns-connection-monitoring' under
the "ns-connection"
* Per NS Endpoint: specified in 'ep-monitoring' under the "ns-
endpoint"
Wu, et al. Expires 30 March 2022 [Page 19]
Internet-Draft IETF Network Slice NBI YANG model September 2021
This model does not define monitoring enabling methods. The
mechanism defined in [RFC8640] and [RFC8641] can be used for either
periodic or on-demand subscription.
By specifying subtree filters or xpath filters to 'ns-connection' or
'ns-endpoint' ,so that only interested contents will be sent. These
mechanisms can be used for monitoring the IETF Network Slice
performance status so that the customer management system could
initiate modification based on the IETF Network Slice running status.
Note: More critical events affecting service delivery need to be
added.
9. IETF Network Slice Service Module
The "ietf-network-slice" module uses types defined in [RFC6991],
[RFC8776].
<CODE BEGINS> file "ietf-network-slice@2021-07-20.yang"
module ietf-network-slice {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-network-slice";
prefix ins;
import ietf-inet-types {
prefix inet;
reference
"RFC 6991: Common YANG Types.";
}
import ietf-yang-types {
prefix yang;
reference
"RFC 6991: Common YANG Types.";
}
import ietf-te-types {
prefix te-types;
reference
"RFC 8776: Common YANG Data Types for Traffic Engineering.";
}
organization
"IETF Traffic Engineering Architecture and Signaling (TEAS)
Working Group";
contact
"WG Web: <https://tools.ietf.org/wg/teas/>
WG List: <mailto:teas@ietf.org>
Editor: Bo Wu <lana.wubo@huawei.com>
: Dhruv Dhody <dhruv.ietf@gmail.com>
Wu, et al. Expires 30 March 2022 [Page 20]
Internet-Draft IETF Network Slice NBI YANG model September 2021
: Reza Rokui <reza.rokui@nokia.com>
: Tarek Saad <tsaad@juniper.net>";
description
"This module contains a YANG module for the IETF Network Slice.
Copyright (c) 2021 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject to
the license terms contained in, the Simplified BSD License set
forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(http://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see the
RFC itself for full legal notices.";
revision 2021-07-20 {
description
"initial version.";
reference
"RFC XXXX: A Yang Data Model for IETF Network Slice Operation";
}
/* Features */
/* Identities */
identity ns-isolation-type {
description
"Base identity for IETF Network slice isolation level.";
}
identity ns-isolation-shared {
base ns-isolation-type;
description
"Shared resources (e.g. queues) are associated with the Network
Slice traffic. Hence, the IETF network slice traffic can be
impacted by effects of other services traffic sharing
the same resources.";
}
identity ns-isolation-dedicated {
base ns-isolation-type;
description
"Dedicated resources (e.g. queues) are associated with the
Network Slice traffic. Hence, the IETF network slice traffic
is isolated from other servceis traffic sharing the same
Wu, et al. Expires 30 March 2022 [Page 21]
Internet-Draft IETF Network Slice NBI YANG model September 2021
resources.";
}
identity ns-security-type {
description
"Base identity for for IETF Network security level.";
}
identity ns-security-authenticate {
base ns-security-type;
description
"IETF Network Slice requires authentication.";
}
identity ns-security-integrity {
base ns-security-type;
description
"IETF Network Slice requires data integrity.";
}
identity ns-security-encryption {
base ns-security-type;
description
"IETF Network Slice requires data encryption.";
}
identity ns-connectivity-type {
description
"Base identity for IETF Network Slice topology.";
}
identity any-to-any {
base ns-connectivity-type;
description
"Identity for any-to-any IETF Network Slice topology.";
}
identity hub-spoke {
base ns-connectivity-type;
description
"Identity for Hub-and-Spoke IETF Network Slice topology.";
}
identity custom {
base ns-connectivity-type;
description
"Identity of a custom NS topology where Hubs can act as
Spoke for certain parts of the network or Spokes as Hubs.";
Wu, et al. Expires 30 March 2022 [Page 22]
Internet-Draft IETF Network Slice NBI YANG model September 2021
}
identity endpoint-role {
description
"Base identity of a NSE role in an IETF Network Slice topology.";
}
identity any-to-any-role {
base endpoint-role;
description
"Identity of any-to-any NS.";
}
identity spoke-role {
base endpoint-role;
description
"A NSE is acting as a Spoke.";
}
identity hub-role {
base endpoint-role;
description
"A NSE is acting as a Hub.";
}
identity ns-slo-metric-type {
description
"Base identity for IETF Network Slice SLO metric type.";
}
identity ns-slo-one-way-bandwidth {
base ns-slo-metric-type;
description
"SLO bandwidth metric. Minimum guaranteed bandwidth between
two endpoints at any time and is measured unidirectionally";
}
identity ns-slo-two-way-bandwidth {
base ns-slo-metric-type;
description
"SLO bandwidth metric. Minimum guaranteed bandwidth between
two endpoints at any time";
}
identity ns-slo-one-way-latency {
base ns-slo-metric-type;
description
"SLO one-way latency is upper bound of network latency when
Wu, et al. Expires 30 March 2022 [Page 23]
Internet-Draft IETF Network Slice NBI YANG model September 2021
transmitting between two endpoints. The metric is defined in
RFC7679";
}
identity ns-slo-two-way-latency {
base ns-slo-metric-type;
description
"SLO two-way latency is upper bound of network latency when
transmitting between two endpoints. The metric is defined in
RFC2681";
}
identity ns-slo-one-way-delay-variation {
base ns-slo-metric-type;
description
"SLO one-way delay variation is defined by RFC3393, is the
difference in the one-way delay between sequential packets
between two endpoints.";
}
identity ns-slo-two-way-delay-variation {
base ns-slo-metric-type;
description
"SLO two-way delay variation is defined by RFC5481, is the
difference in the round-trip delay between sequential packets
between two endpoints.";
}
identity ns-slo-one-way-packet-loss {
base ns-slo-metric-type;
description
"SLO loss metric. The ratio of packets dropped to packets
transmitted between two endpoints in one-way
over a period of time as specified in RFC7680";
}
identity ns-slo-two-way-packet-loss {
base ns-slo-metric-type;
description
"SLO loss metric. The ratio of packets dropped to packets
transmitted between two endpoints in two-way
over a period of time as specified in RFC7680";
}
identity ns-slo-availability {
base ns-slo-metric-type;
description
"SLO availability level.";
Wu, et al. Expires 30 March 2022 [Page 24]
Internet-Draft IETF Network Slice NBI YANG model September 2021
}
identity ns-match-type {
description
"Base identity for IETF Network Slice traffic match type.";
}
identity ns-phy-interface-match {
base ns-match-type;
description
"Use the physical interface as match criteria for the IETF
Network Slice traffic.";
}
identity ns-vlan-match {
base ns-match-type;
description
"Use the VLAN ID as match criteria for the IETF Network Slice
traffic.";
}
identity ns-label-match {
base ns-match-type;
description
"Use the MPLS label as match criteria for the IETF Network
Slice traffic.";
}
identity peering-protocol-type {
description
"Base identity for NSE peering protocol type.";
}
identity peering-protocol-bgp {
base peering-protocol-type;
description
"Use BGP as protocol for NSE peering with customer device.";
}
identity peering-static-routing {
base peering-protocol-type;
description
"Use static routing for NSE peering with customer device.";
}
/*
* Identity for availability-type
*/
Wu, et al. Expires 30 March 2022 [Page 25]
Internet-Draft IETF Network Slice NBI YANG model September 2021
identity availability-type {
description
"Base identity from which specific availability types are
derived.";
}
identity level-1 {
base availability-type;
description
"level 1: 99.9999%";
}
identity level-2 {
base availability-type;
description
"level 2: 99.999%";
}
identity level-3 {
base availability-type;
description
"level 3: 99.99%";
}
identity level-4 {
base availability-type;
description
"level 4: 99.9%";
}
identity level-5 {
base availability-type;
description
"level 5: 99%";
}
/* typedef */
typedef operational-type {
type enumeration {
enum up {
value 0;
description
"Operational status UP.";
}
enum down {
value 1;
description
Wu, et al. Expires 30 March 2022 [Page 26]
Internet-Draft IETF Network Slice NBI YANG model September 2021
"Operational status DOWN.";
}
enum unknown {
value 2;
description
"Operational status UNKNOWN.";
}
}
description
"This is a read-only attribute used to determine the
status of a particular element.";
}
typedef ns-monitoring-type {
type enumeration {
enum one-way {
description
"Represents one-way measurments monitoring type.";
}
enum two-way {
description
"represents two-way measurements monitoring type.";
}
}
description
"An enumerated type for monitoring on a IETF Network Slice
connection.";
}
/* Groupings */
grouping status-params {
description
"A grouping used to join operational and administrative status.";
container status {
description
"A container for the administrative and operational state.";
leaf admin-enabled {
type boolean;
description
"The administrative status.";
}
leaf oper-status {
type operational-type;
config false;
description
"The operational status.";
}
Wu, et al. Expires 30 March 2022 [Page 27]
Internet-Draft IETF Network Slice NBI YANG model September 2021
}
}
grouping ns-match-criteria {
description
"A grouping for the IETF Network Slice match definition.";
container ns-match-criteria {
description
"Describes the IETF Network Slice match criteria.";
list ns-match-criterion {
key "match-type";
description
"List of the IETF Network Slice traffic match criteria.";
leaf match-type {
type identityref {
base ns-match-type;
}
description
"Identifies an entry in the list of the IETF Network Slice
match criteria.";
}
list values {
key "index";
description
"List of match criteria values.";
leaf index {
type uint8;
description
"Index of an entry in the list.";
}
leaf value {
type string;
description
"Describes the IETF Network Slice match criteria, e.g.
IP address, VLAN, etc.";
}
}
}
}
}
grouping ns-connection-group-metric-bounds {
description
"Grouping of Network Slice metric bounds that
are shared amongst multiple connections of a Network
Slice.";
leaf ns-slo-shared-bandwidth {
type te-types:te-bandwidth;
Wu, et al. Expires 30 March 2022 [Page 28]
Internet-Draft IETF Network Slice NBI YANG model September 2021
description
"A limit on the bandwidth that is shared amongst
multiple connections of an IETF Network Slice.";
}
}
grouping ns-sles {
description
"Indirectly Measurable Objectives of a IETF Network
Slice.";
leaf-list security {
type identityref {
base ns-security-type;
}
description
"The IETF Network Slice security SLE(s)";
}
leaf isolation {
type identityref {
base ns-isolation-type;
}
default "ns-isolation-shared";
description
"The IETF Network Slice isolation SLE requirement.";
}
leaf max-occupancy-level {
type uint8 {
range "1..100";
}
description
"The maximal occupancy level specifies the number of flows to
be admitted.";
}
leaf mtu {
type uint16;
units "bytes";
mandatory true;
description
"The MTU specifies the maximum length in octets of data
packets that can be transmitted by the NS. The value needs
to be less than or equal to the minimum MTU value of
all 'ep-network-access-points' in the NSEs of the NS. ";
}
container steering-constraints {
description
"Container for the policy of steering constraints
applicable to IETF Network Slice.";
container path-constraints {
Wu, et al. Expires 30 March 2022 [Page 29]
Internet-Draft IETF Network Slice NBI YANG model September 2021
description
"Container for the policy of path constraints
applicable to IETF Network Slice.";
}
container service-function {
description
"Container for the policy of service function
applicable to IETF Network Slice.";
}
}
}
grouping ns-metric-bounds {
description
"IETF Network Slice metric bounds grouping.";
container ns-metric-bounds {
description
"IETF Network Slice metric bounds container.";
list ns-metric-bound {
key "metric-type";
description
"List of IETF Network Slice metric bounds.";
leaf metric-type {
type identityref {
base ns-slo-metric-type;
}
description
"Identifies an entry in the list of metric type
bounds for the IETF Network Slice.";
}
leaf metric-unit {
type string;
mandatory true;
description
"The metric unit of the parameter. For example,
s, ms, ns, and so on.";
}
leaf value-description {
type string;
description
"The description of previous value. ";
}
leaf bound {
type uint64;
default "0";
description
"The Bound on the Network Slice connection metric. A
zero indicate an unbounded upper limit for the
Wu, et al. Expires 30 March 2022 [Page 30]
Internet-Draft IETF Network Slice NBI YANG model September 2021
specific metric-type.";
}
}
}
}
grouping ep-peering {
description
"A grouping for the IETF Network Slice Endpoint peering.";
container ep-peering {
description
"Describes NSE peering attributes.";
list protocol {
key "protocol-type";
description
"List of the NSE peering protocol.";
leaf protocol-type {
type identityref {
base peering-protocol-type;
}
description
"Identifies an entry in the list of NSE peering
protocol type.";
}
list attribute {
key "index";
description
"List of protocol attribute.";
leaf index {
type uint8;
description
"Index of an entry in the list.";
}
leaf attribute-description {
type string;
description
"The description of the attribute. ";
}
leaf value {
type string;
description
"Describes the value of protocol attribute, e.g.
nexthop address, peer address, etc.";
}
}
}
}
}
Wu, et al. Expires 30 March 2022 [Page 31]
Internet-Draft IETF Network Slice NBI YANG model September 2021
grouping ep-network-access-points {
description
"Grouping for the endpoint network access definition.";
container ep-network-access-points {
description
"List of network access points.";
list ep-network-access-point {
key "network-access-id";
description
"The IETF Network Slice network access points
related parameters.";
leaf network-access-id {
type string;
description
"Uniquely identifier a network access point.";
}
leaf network-access-description {
type string;
description
"The network access point description.";
}
leaf network-access-node-id {
type string;
description
"The network access point node ID in the case of
multi-homing.";
}
leaf network-access-tp-id {
type string;
description
"The termination port ID of the EP network access
point.";
}
leaf network-access-tp-ip {
type inet:host;
description
"The IP address of the EP network access point.";
}
leaf mtu {
type uint16;
units "bytes";
mandatory true;
description
"Maximum size in octets of a data packet that
can traverse a NSE network access point. ";
}
/* Per ep-network-access-point rate limits */
uses ns-rate-limit;
Wu, et al. Expires 30 March 2022 [Page 32]
Internet-Draft IETF Network Slice NBI YANG model September 2021
}
}
}
grouping endpoint-monitoring-parameters {
description
"Grouping for the endpoint monitoring parameters.";
container ep-monitoring {
config false;
description
"Container for endpoint monitoring parameters.";
leaf incoming-utilized-bandwidth {
type te-types:te-bandwidth;
description
"Incoming bandwidth utilization at an endpoint.";
}
leaf incoming-bw-utilization {
type decimal64 {
fraction-digits 5;
range "0..100";
}
units "percent";
mandatory true;
description
"To be used to define the bandwidth utilization
as a percentage of the available bandwidth.";
}
leaf outgoing-utilized-bandwidth {
type te-types:te-bandwidth;
description
"Outoing bandwidth utilization at an endpoint.";
}
leaf outgoing-bw-utilization {
type decimal64 {
fraction-digits 5;
range "0..100";
}
units "percent";
mandatory true;
description
"To be used to define the bandwidth utilization
as a percentage of the available bandwidth.";
}
}
}
grouping common-monitoring-parameters {
description
Wu, et al. Expires 30 March 2022 [Page 33]
Internet-Draft IETF Network Slice NBI YANG model September 2021
"Grouping for link-monitoring-parameters.";
leaf latency {
type yang:gauge64;
units "usec";
description
"The latency statistics per Network Slice connection.
RFC2681 and RFC7679 discuss round trip times and one-way
metrics, respectively";
}
leaf jitter {
type yang:gauge32;
description
"The jitter statistics per Network Slice member
as defined by RFC3393.";
}
leaf loss-ratio {
type decimal64 {
fraction-digits 6;
range "0 .. 50.331642";
}
description
"Packet loss as a percentage of the total traffic
sent over a configurable interval. The finest precision is
0.000003%. where the maximum 50.331642%.";
reference
"RFC 7810, section-4.4";
}
}
grouping geolocation-container {
description
"A grouping containing a GPS location.";
container location {
description
"A container containing a GPS location.";
leaf altitude {
type int64;
units "millimeter";
description
"Distance above the sea level.";
}
leaf latitude {
type decimal64 {
fraction-digits 8;
range "-90..90";
}
description
"Relative position north or south on the Earth's surface.";
Wu, et al. Expires 30 March 2022 [Page 34]
Internet-Draft IETF Network Slice NBI YANG model September 2021
}
leaf longitude {
type decimal64 {
fraction-digits 8;
range "-180..180";
}
description
"Angular distance east or west on the Earth's surface.";
}
}
// gps-location
}
// geolocation-container
grouping ns-rate-limit {
description
"The Network Slice rate limit grouping.";
container ep-rate-limit {
description
"Container for the asymmetric traffic control";
leaf incoming-rate-limit {
type te-types:te-bandwidth;
description
"The rate-limit imposed on incoming traffic.";
}
leaf outgoing-rate-limit {
type te-types:te-bandwidth;
description
"The rate-limit imposed on outgoing traffic.";
}
}
}
grouping endpoint {
description
"IETF Network Slice endpoint related information";
leaf ep-id {
type string;
description
"unique identifier for the referred IETF Network
Slice endpoint";
}
leaf ep-description {
type string;
description
"endpoint name";
}
Wu, et al. Expires 30 March 2022 [Page 35]
Internet-Draft IETF Network Slice NBI YANG model September 2021
leaf ep-role {
type identityref {
base endpoint-role;
}
default "any-to-any-role";
description
"Role of the endpoint in the IETF Network Slice.";
}
uses geolocation-container;
leaf node-id {
type string;
description
"Uniquely identifies an edge node within the IETF slice
network.";
}
leaf ep-ip {
type inet:host;
description
"The address of the endpoint IP address.";
}
uses ns-match-criteria;
uses ep-peering;
uses ep-network-access-points;
uses ns-rate-limit;
/* Per NSE rate limits */
uses status-params;
uses endpoint-monitoring-parameters;
}
//ns-endpoint
grouping ns-connection {
description
"The Network Slice connection is described in this container.";
leaf ns-connection-id {
type uint32;
description
"The Network Slice connection identifier";
}
leaf ns-connection-description {
type string;
description
"The Network Slice connection description";
}
container src {
description
"the source of Network Slice link";
leaf src-ep-id {
Wu, et al. Expires 30 March 2022 [Page 36]
Internet-Draft IETF Network Slice NBI YANG model September 2021
type leafref {
path "/network-slices/network-slice"
+ "/ns-endpoints/ns-endpoint/ep-id";
}
description
"reference to source Network Slice endpoint";
}
}
container dest {
description
"the destination of Network Slice link ";
leaf dest-ep-id {
type leafref {
path "/network-slices/network-slice"
+ "/ns-endpoints/ns-endpoint/ep-id";
}
description
"reference to dest Network Slice endpoint";
}
}
uses ns-slo-sle-policy;
/* Per connection ns-slo-sle-policy overrides
* the per network slice ns-slo-sle-policy.
*/
leaf monitoring-type {
type ns-monitoring-type;
description
"One way or two way monitoring type.";
}
container ns-connection-monitoring {
config false;
description
"SLO status Per network-slice endpoint to endpoint ";
uses common-monitoring-parameters;
}
}
//ns-connection
grouping slice-template {
description
"Grouping for slice-templates.";
container ns-slo-sle-templates {
description
"Contains a set of network slice templates to
reference in the IETF network slice.";
list ns-slo-sle-template {
key "id";
Wu, et al. Expires 30 March 2022 [Page 37]
Internet-Draft IETF Network Slice NBI YANG model September 2021
leaf id {
type string;
description
"Identification of the Service Level Objective (SLO)
and Service Level Expectation (SLE) template to be used.
Local administration meaning.";
}
leaf template-description {
type string;
description
"Description of the SLO & SLE policy template.";
}
description
"List for SLO and SLE template identifiers.";
}
}
}
/* Configuration data nodes */
grouping ns-slo-sle-policy {
description
"Network Slice policy grouping.";
choice ns-slo-sle-policy {
description
"Choice for SLO and SLE policy template.
Can be standard template or customized template.";
case standard {
description
"Standard SLO template.";
leaf slo-sle-template {
type leafref {
path "/network-slices"
+ "/ns-slo-sle-templates/ns-slo-sle-template/id";
}
description
"Standard SLO and SLE template to be used.";
}
}
case custom {
description
"Customized SLO template.";
container slo-sle-policy {
description
"Contains the SLO policy.";
leaf policy-description {
type string;
description
Wu, et al. Expires 30 March 2022 [Page 38]
Internet-Draft IETF Network Slice NBI YANG model September 2021
"Description of the SLO policy.";
}
uses ns-metric-bounds;
uses ns-sles;
}
}
}
}
container network-slices {
description
"IETF network-slice configurations";
uses slice-template;
list network-slice {
key "ns-id";
description
"a network-slice is identified by a ns-id";
leaf ns-id {
type string;
description
"A unique network-slice identifier across an IETF NSC ";
}
leaf ns-description {
type string;
description
"Give more description of the network slice";
}
leaf-list customer-name {
type string;
description
"List of the customer that actually uses the slice.
In the case that multiple customers sharing
same slice service, e.g., 5G, customer name may
help with operational management";
}
leaf ns-connectivity-type {
type identityref {
base ns-connectivity-type;
}
default "any-to-any";
description
"Network Slice topology.";
}
uses ns-slo-sle-policy;
uses status-params;
container ns-endpoints {
description
"Endpoints";
Wu, et al. Expires 30 March 2022 [Page 39]
Internet-Draft IETF Network Slice NBI YANG model September 2021
list ns-endpoint {
key "ep-id";
uses endpoint;
description
"List of endpoints in this slice";
}
}
container ns-connections {
description
"Connections container";
list ns-connection {
key "ns-connection-id";
description
"List of Network Slice connections.";
uses ns-connection;
}
}
}
//ietf-network-slice list
}
}
<CODE ENDS>
10. Security Considerations
The YANG module defined in this document is designed to be accessed
via network management protocols such as NETCONF [RFC6241] or
RESTCONF [RFC8040]. 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 [RFC8446].
The NETCONF access control model [RFC8341] 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.
o /ietf-network-slice/network-slices/network-slice
Wu, et al. Expires 30 March 2022 [Page 40]
Internet-Draft IETF Network Slice NBI YANG model September 2021
The entries in the list above include the whole network
configurations corresponding with the slice which the higher
management system requests, and indirectly create or modify the PE or
P device configurations. Unexpected changes to these entries could
lead to service disruption and/or network misbehavior.
11. IANA Considerations
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-slice
Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace.
This document requests to register a YANG module in the YANG Module
Names registry [RFC7950].
Name: ietf-network-slice
Namespace: urn:ietf:params:xml:ns:yang:ietf-network-slice
Prefix: ins
Reference: RFC XXXX
12. Acknowledgments
The authors wish to thank Mohamed Boucadair, Kenichi Ogaki, Sergio
Belotti, Qin Wu, Susan Hares, Eric Grey, and many others for their
helpful comments and suggestions.
13. References
13.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<https://www.rfc-editor.org/info/rfc3688>.
[RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
and A. Bierman, Ed., "Network Configuration Protocol
(NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
<https://www.rfc-editor.org/info/rfc6241>.
Wu, et al. Expires 30 March 2022 [Page 41]
Internet-Draft IETF Network Slice NBI YANG model September 2021
[RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure
Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011,
<https://www.rfc-editor.org/info/rfc6242>.
[RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types",
RFC 6991, DOI 10.17487/RFC6991, July 2013,
<https://www.rfc-editor.org/info/rfc6991>.
[RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
RFC 7950, DOI 10.17487/RFC7950, August 2016,
<https://www.rfc-editor.org/info/rfc7950>.
[RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
<https://www.rfc-editor.org/info/rfc8040>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
<https://www.rfc-editor.org/info/rfc8340>.
[RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration
Access Control Model", STD 91, RFC 8341,
DOI 10.17487/RFC8341, March 2018,
<https://www.rfc-editor.org/info/rfc8341>.
[RFC8342] Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
and R. Wilton, "Network Management Datastore Architecture
(NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018,
<https://www.rfc-editor.org/info/rfc8342>.
[RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol
Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
<https://www.rfc-editor.org/info/rfc8446>.
[RFC8640] Voit, E., Clemm, A., Gonzalez Prieto, A., Nilsen-Nygaard,
E., and A. Tripathy, "Dynamic Subscription to YANG Events
and Datastores over NETCONF", RFC 8640,
DOI 10.17487/RFC8640, September 2019,
<https://www.rfc-editor.org/info/rfc8640>.
[RFC8641] Clemm, A. and E. Voit, "Subscription to YANG Notifications
for Datastore Updates", RFC 8641, DOI 10.17487/RFC8641,
September 2019, <https://www.rfc-editor.org/info/rfc8641>.
Wu, et al. Expires 30 March 2022 [Page 42]
Internet-Draft IETF Network Slice NBI YANG model September 2021
[RFC8776] Saad, T., Gandhi, R., Liu, X., Beeram, V., and I. Bryskin,
"Common YANG Data Types for Traffic Engineering",
RFC 8776, DOI 10.17487/RFC8776, June 2020,
<https://www.rfc-editor.org/info/rfc8776>.
13.2. Informative References
[I-D.geng-teas-network-slice-mapping]
Geng, X., Dong, J., Pang, R., Han, L., Niwa, T., Jin, J.,
Liu, C., and N. Nageshar, "5G End-to-end Network Slice
Mapping from the view of Transport Network", Work in
Progress, Internet-Draft, draft-geng-teas-network-slice-
mapping-03, 22 February 2021,
<https://www.ietf.org/archive/id/draft-geng-teas-network-
slice-mapping-03.txt>.
[I-D.ietf-opsawg-vpn-common]
Barguil, S., Dios, O. G. D., Boucadair, M., and Q. Wu, "A
Layer 2/3 VPN Common YANG Model", Work in Progress,
Internet-Draft, draft-ietf-opsawg-vpn-common-11, 23
September 2021, <https://www.ietf.org/archive/id/draft-
ietf-opsawg-vpn-common-11.txt>.
[I-D.ietf-teas-actn-vn-yang]
Lee, Y., Dhody, D., Ceccarelli, D., Bryskin, I., and B. Y.
Yoon, "A YANG Data Model for VN Operation", Work in
Progress, Internet-Draft, draft-ietf-teas-actn-vn-yang-12,
25 August 2021, <https://www.ietf.org/archive/id/draft-
ietf-teas-actn-vn-yang-12.txt>.
[I-D.ietf-teas-ietf-network-slices]
Farrel, A., Gray, E., Drake, J., Rokui, R., Homma, S.,
Makhijani, K., Contreras, L. M., and J. Tantsura,
"Framework for IETF Network Slices", Work in Progress,
Internet-Draft, draft-ietf-teas-ietf-network-slices-04, 23
August 2021, <https://www.ietf.org/archive/id/draft-ietf-
teas-ietf-network-slices-04.txt>.
[RFC8309] Wu, Q., Liu, W., and A. Farrel, "Service Models
Explained", RFC 8309, DOI 10.17487/RFC8309, January 2018,
<https://www.rfc-editor.org/info/rfc8309>.
[RFC8453] Ceccarelli, D., Ed. and Y. Lee, Ed., "Framework for
Abstraction and Control of TE Networks (ACTN)", RFC 8453,
DOI 10.17487/RFC8453, August 2018,
<https://www.rfc-editor.org/info/rfc8453>.
Wu, et al. Expires 30 March 2022 [Page 43]
Internet-Draft IETF Network Slice NBI YANG model September 2021
[RFC8795] Liu, X., Bryskin, I., Beeram, V., Saad, T., Shah, H., and
O. Gonzalez de Dios, "YANG Data Model for Traffic
Engineering (TE) Topologies", RFC 8795,
DOI 10.17487/RFC8795, August 2020,
<https://www.rfc-editor.org/info/rfc8795>.
Appendix A. IETF Network Slice NBI Model Usage Example
The following example describes a simplified service configuration of
two IETF Network slice instances:
* IETF Network Slice 1 on Device1, Device3, and Device4, with any-
to-any connectivity type
* IETF Network Slice 2 on Device2, Device3, with any-to-any
connectivity type
192.0.2.2 VLAN1
+--------+
|Device1 o------/
+--------+ | +------+
+--------+ +------o| A +---------------+
|Device2 o-------/-----o| | |
+--------+ +---+--+ |
198.51.100.2 | |
VLAN2 | +---+--+ 192.0.2.4 VLAN1
| | | +--------+
192.0.2.3 VLAN1 | | C o-----/-----oDevice4 |
+--------+ | +---+--+ +--------+
| o------/ | |
| | | +---+--+ |
| Device3| +------o| B +---------------+
| o-------/-----o| |
+--------+ +------+
198.51.100.3
VLAN2
POST: /restconf/data/ietf-network-slice:ietf-network-slices
Host: example.com
Content-Type: application/yang-data+json
{
"network-slices":{
"network-slice":[
{
"ns-id":"1",
"ns-description":"slice1",
"ns-connectivity-type":"any-to-any",
Wu, et al. Expires 30 March 2022 [Page 44]
Internet-Draft IETF Network Slice NBI YANG model September 2021
"ns-endpoints":{
"ns-endpoint":[
{
"ep-id":"11",
"ep-description":"slice1 ep1 connected to device 1",
"ep-role":"any-to-any-role",
"ns-match-criteria":[
{
"match-type":"ns-vlan-match",
"value":[
{
"index":"1",
"value":"1"
}
]
}
]
},
{
"ep-id":"12",
"ep-description":"slice1 ep2 connected to device 3",
"ep-role":"any-to-any-role",
"ns-match-criteria":[
{
"match-type":"ns-vlan-match",
"value":[
{
"index":"1",
"value":"20"
}
]
}
]
},
{
"ep-id":"13",
"ep-description":"slice1 ep3 connected to device 4",
"ep-role":"any-to-any-role",
"ns-match-criteria":[
{
"match-type":"ns-vlan-match",
"value":[
{
"index":"1",
"value":"1"
}
]
}
Wu, et al. Expires 30 March 2022 [Page 45]
Internet-Draft IETF Network Slice NBI YANG model September 2021
]
}
]
}
},
{
"ns-id":"ns2",
"ns-description":"slice2",
"ns-connectivity-type":"any-to-any",
"ns-endpoints":{
"ns-endpoint":[
{
"ep-id":"21",
"ep-description":"slice2 ep1 connected to device 2",
"ep-role":"any-to-any-role",
"ns-match-criteria":[
{
"match-type":"ns-vlan-match",
"value":[
{
"index":"1",
"value":"2"
}
]
}
]
},
{
"ep-id":"22",
"ep-description":"slice2 ep2 connected to device 3",
"ep-role":"any-to-any-role",
"ns-match-criteria":[
{
"match-type":"ns-vlan-match",
"value":[
{
"index":"1",
"value":"2"
}
]
}
]
}
]
}
}
]
}
Wu, et al. Expires 30 March 2022 [Page 46]
Internet-Draft IETF Network Slice NBI YANG model September 2021
}
Appendix B. Appendix B IETF Network Slice Match Criteria
5G is a use case of the IETF Network Slice and 5G End-to-end Network
Slice Mapping from the view of IETF
Network[I-D.geng-teas-network-slice-mapping]
defines two types of Network Slice interconnection and
differentiation methods: by physical interface or by TNSII (Transport
Network Slice Interworking Identifier). TNSII is a field in the
packet header when different 5G wireless network slices are
transported through a single physical interfaces of the IETF scoped
Network. In the 5G scenario, "network-slice-match-criteria" refers
to TNSII.
+------------------------------------------------------------+
| 5G E2E network slice orchestrator |
++-----------------------------------------------------+-----+
| | |
| IETF Network Slice NBI |
+---+-------+ | +-----+-----+
| | +------------------+ | |
|RAN Slice | |IETF Network Slice| |Core Slice |
|controller | | controller | | controller|
+----+------+ +-------+----------+ +-----+-----+
| | |
| | |
+---+--+ +------------+----------------+ ++-----+
| | | | | |
| | | | | |
|+----+| | | | |
|| ||NS1-NSE1 | Network Slice 1 | |+----+|
||gNB1|+---------+-----+-----------------------+--------+|UPF1||
|| |+************ / |NS1-NSE3|+----+|
|+----+|NS2-NSE1 | */ | | |
| | /* | | |
|+----+|NS1-NSE2 | / * | | |
|| |+---------- * Network Slice 2 |NS2-NSE3|+----+|
||gNB2|+************************************************+|UPF2||
|| ||NS2-NSE2 | | |+----+|
|+----+| | | |
| | | | | |
| | | | | |
+------+ +----------- -----------------+ +------+
Wu, et al. Expires 30 March 2022 [Page 47]
Internet-Draft IETF Network Slice NBI YANG model September 2021
As shown in the figure, gNodeB 1 and gNodeB 2 use IP gNB1 and IP gNB2
to communicate with the IETF network, respectively. In addition, the
traffic of NS1 and NS2 on gNodeB 1 and gNodeB 2 is transmitted
through the same access links to the IETF slice network. The IETF
slice network need to to distinguish different IETF Network Slice
traffic of same gNB. Therefore, in addition to using "node-id" and
"ep-ip" to identify a Network Slice Endpont, other information is
needed along with these parameters to uniquely distinguish a NSE.
For example, VLAN IDs in the user traffic can be used to distinguish
the NSEs of gNBs and UPFs.
Authors' Addresses
Bo Wu
Huawei Technologies
101 Software Avenue, Yuhua District
Nanjing
Jiangsu, 210012
China
Email: lana.wubo@huawei.com
Dhruv Dhody
Huawei Technologies
Divyashree Techno Park
Bangalore 560066
Karnataka
India
Email: dhruv.ietf@gmail.com
Reza Rokui
Nokia
Email: reza.rokui@nokia.com
Tarek Saad
Juniper Networks
Email: tsaad@juniper.net
Wu, et al. Expires 30 March 2022 [Page 48]
Internet-Draft IETF Network Slice NBI YANG model September 2021
Liuyan Han
China Mobile
Email: hanliuyan@chinamobile.com
Luis Miguel Contreras
Telefonica
Distrito T
28050 Madrid
Spain
Email: luismiguel.contrerasmurillo@telefonica.com
Wu, et al. Expires 30 March 2022 [Page 49]
