Internet-Draft IETF Network Slicing June 2023
Boucadair Expires 14 December 2023 [Page]
Workgroup:
Traffic Engineering Architecture and Signaling
Internet-Draft:
draft-boucadair-teas-ietf-slicing-overview-01
Published:
Intended Status:
Informational
Expires:
Author:
M. Boucadair
Orange

An Overview of IETF Network Slicing Efforts

Abstract

This document lists a set of slicing-related specifications that are being development within the IETF. This document is meant to provide an overview of slicing activities in the IETF to hopefully ease coordination and ensure that specifications that are developed in many WGs are consistent.

Discussion Venues

This note is to be removed before publishing as an RFC.

Discussion of this document takes place on the Traffic Engineering Architecture and Signaling Working Group mailing list (teas@ietf.org), which is archived at https://mailarchive.ietf.org/arch/browse/teas/.

Source for this draft and an issue tracker can be found at https://github.com/boucadair/ietf-slice-overview.

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 14 December 2023.

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Table of Contents

1. Introduction

Various slicing efforts are being conduced within various IETF WGs (e.g., teas, idr, spring, ccamp, mpls, opsawg, 6man, and ippm) and areas (e.g., rtg, int, tsv, and ops). All these efforts are referring to the IETF framework that is developed by the teas WG (Section 2), however there is a lack of a global visibility about these efforts and their interdependency.

Also, there is a lack of cross-WG communications in some cases when a slicing-related specification is candidate for adoption or adopted by a WG. This lack of global view at the IETF level and lack of early cross-WG communications may induce some inconsistency. For example, some proposals argue in favor of specifying extensions to convey specific identifiers in packets. However, distinct identifiers are being proposed: slice identifier, NRP Selector, NRP identifier, VTN identifier, VTN resource identifier, etc. The need and relationship between these identifiers are worth to be discussed independent of the channels that are used to convey these identifiers.

This document provides an overview of slicing activities in the IETF to hopefully ease coordination and ensure that specifications that are developed in many WGs are consistent, e.g.:

Future versions of this document many include recommendations.

2. Reference Framework and Architecture

[I-D.ietf-teas-ietf-network-slices] is the authoritative IETF framework for Network Slices. It provides definitions for a slice-related core terms and specifies a framework for the provision of Network Slice services over networks that are deployed using technologies that are owned by the IETF (IP, MPLS, etc.). The document refers to such slices as IETF Network Slice.

[I-D.ietf-teas-ietf-network-slices] provides a clear distinction between:

The IETF Network Slice service is specified in terms of:

The service objectives can be expressed as Service Level Objectives (SLOs) or Service Level Expectations (SLEs).

In some deploymenets, the underlying network can be customized to select a subset of resources that are suitable for the delivery of an IETF Network Slice service. Such a customization can be achieved by creating a set of Network Resource Partitions (NRPs).

In other deployments, IETF Network Slices can be hosted directly on the underlay network (i.e., without requiring any NRP).

IETF Network Slices can be realized using existing tools (Section 3.1). The extensions listed in Section 6 or Section 7 are not required in such a case.

[I-D.ietf-teas-ietf-network-slices] does not provide any recommendation about the technological means to realize an IETF Network Slice service. These considerations are deployment specific.

3. Models for Realizing Network Slices

3.1. Using Current IP/MPLS Technologies

[I-D.srld-teas-5g-slicing] describes a model for the realization of IETF Network Slices for 5G networks. This realization model reuses many building blocks that are commonly used in service provider networks, specifically:

  • L2VPN/L3VPN service instances for logical separation,
  • Fine-grained resource control at the PE,
  • Coarse resource control at the transit, and
  • Capacity planning/management for efficient usage of provider network resources.

3.2. Using Network Resource Partitions and Slice-Flow Aggregates

[I-D.ietf-teas-ns-ip-mpls] proposes a model that is inspired from the Diffserv model for the realization of Network Slices over IP/MPLS networks. Specifically, this model introduces the concept of Slice-Flow Aggregate which is defined as a collection of packets that are mapped to an NRP and are given the same forwarding treatment in a shared network. An aggregate can group flows from of one or more IETF Network Slice services.

[I-D.ietf-teas-ns-ip-mpls] also introduces the notion of NRP Policy that is used to trigger the creation of NRPs that will support a given Slice-Flow Aggregate. In some deployment schemes, packets that belong to a Slice-Flow Aggregate are forwarded by intermediate node along the appropriate NRP by processing an NRP Selector that is carried by these packets.

3.3. Optical Transport Networks (OTN) Slicing

[I-D.ietf-ccamp-yang-otn-slicing] defines Optical Transport Networks (OTN) slice as an OTN virtual network topology connecting a number of OTN endpoints using a set of shared or dedicated OTN network resources to satisfy specific SLOs. OTN slices are considered as a technology-specific realization of an IETF Network Slice in the OTN domain.

3.4. VPN+

[I-D.ietf-teas-enhanced-vpn] describes a framework for providing enhanced VPN services based upon VPN and Traffic Engineering (TE) technologies. Enhanced VPN (VPN+) can be used for the realization of IETF network slices. This document introduces the concept of Virtual Transport Network (VTN), which is a virtual underlay network consisting of a subset of network resources allocated from the physical underlay network, and is associated with a customized network topology.

3.5. Instantiation in Service Providers Networks

[I-D.barguil-teas-network-slices-instantation] focuses on the instantiation of the IETF Network Slice services in service provider networks using available data models. In particular, this document describes the relationship between service models for managing the IETF Network Slice services and Network Models (e.g., the Layer-3 Network Model (L3NPM, [RFC9182]), the Layer-2 Network Model (L2NM [RFC9291])) used for the realization of the slices.

3.6. Structuring Network Slice Controllers

[I-D.contreras-teas-slice-controller-models] proposes an approach for structuring the IETF Network Slice Controller as well as how to use different data models being defined for IETF Network Slice Service provision.

3.7. SR-based Hierarchical Network Slices

[I-D.gong-teas-hierarchical-slice-solution] proposes a hierarchical approach for realizing IETF Network Slices in Segment Routing domain. The approach involves two levels:

  • Level 1 Network Slices are realized using Flex-Algo.
  • Level 2 forwarding paths are restricted in the Level 1 topology by using SR Policy and NRP-ID in the data plane.

3.8. Realization of Composite Network Slices

[I-D.li-teas-composite-network-slices] investigates a set of scenarios for realizing composite IETF Network Slices (that basically involve other slices). The document defines a new identifier, called Inter-Domain Network Resource Partition Identifier (Inter-domain NRP ID).

4. Applicability and Mapping Scenarios

4.1. 3GPP 5G End-to-End Network Slices

[I-D.ietf-teas-5g-network-slice-application] focuses on the application of IETF Network Slices in the context of the 3GPP 5G slices.

4.3. Mobility-Aware Transport Network Slicing

[I-D.ietf-dmm-tn-aware-mobility] discusses a mapping of 5G slices to IETF Network Slices when the transport network is separated from the networks in which the 5G network functions are deployed (e.g., 5G functions distributed across data centers). This document zooms into the use of UDP source port number in GTP-U outer header and LAN to map between a 5G slice and corresponding IETF Network Slice segments that is listed in [I-D.ietf-teas-5g-network-slice-application].

4.4. DetNet

[I-D.sw-detnet-network-slice-mapping-yang] describes the applicability of DetNet to IETF Network Slice, particularly to provide deterministic services. The document describes how to use DetNet flow aggregation as the Slice-Flow Aggregates over an underlying NRP following the approach in Section 3.2.

5. Orchestration and Data Models

Figure 1 provides an example of the various data models that can be invoked in the context of Network Slicing.

                              +---------------+
                               |   Customer    |
                               +-------+-------+
               Customer Service Model  |
               e.g., slice-svc, ac-svc,| and bearer-svc
                               +-------+-------+
                               |    Service    |
                               | Orchestration |
                               +-------+-------+
                Network Model          |
  e.g., l2vpn-ntw, l3vpn-ntw, sap, and | ac-ntw
                               +-------+-------+
                               |   Network     |
                               | Orchestration |
                               +-------+-------+
         Network Configuration Model   |
                           +-----------+-----------+
                           |                       |
                  +--------+------+       +--------+------+
                  |    Domain     |       |     Domain    |
                  | Orchestration |       | Orchestration |
                  +---+-----------+       +--------+------+
       Device         |        |                   |
       Configuration  |        |                   |
       Model          |        |                   |
                 +----+----+   |                   |
                 | Config  |   |                   |
                 | Manager |   |                   |
                 +----+----+   |                   |
                      |        |                   |
                      | NETCONF/CLI..................
                      |        |                   |
                    +--------------------------------+
      +----+ Bearer |                                | Bearer +----+
      |CE#1+--------+            Network             +--------+CE#2|
      +----+   AC   |                                |   AC   +----+
                    +--------------------------------+
       Site A                                                  Site B
Figure 1: Overview of Data Models used for Network Slicing

5.1. Common Models

[RFC9181] specifies a set of reusable types and groupings to manage VPN services. Note that VPNs are used for the realization of Network Slices.

[I-D.boro-opsawg-teas-common-ac] specifies a set of reusable types and groupings to manage Attachment Circuits (ACs).

5.2. Service Models

5.2.1. Attachment Circuit as a Service (ACaaS) Data Model

[I-D.boro-opsawg-teas-attachment-circuit] specifies YANG data models for managing 'Attachment Circuits'-as-a-Service (ACaaS) and also bearers. These ACs and bearers are used to identify where to deliver a slice service.

5.2.2. Network Slice Service Data Model

[I-D.ietf-teas-ietf-network-slice-nbi-yang] defines a YANG data model for manaing IETF Network Slice Services.

5.3. Network Models

5.3.1. Service Attachment Points (SAPs)

[I-D.ietf-opsawg-sap] defines a YANG data model for representing an abstract view of the provider network topology that contains the points from which its services can be attached (e.g., basic connectivity, VPN, network slices). Also, the model can be used to retrieve the points where the services are actually being delivered to customers (including peer networks).

A SAP network topology can be used for one or multiple service types ('service-type'). Setting this data node to 'network-slice' allows a controller to expose where IETF Network Slices services are being delivered. It can also be used to check where IETF Network Slice services can be delivered.

5.3.2. AC-augmented SAPs

[I-D.boro-opsawg-ntw-attachment-circuit] augments the SAP model with more details for managing ACs at the network level.

5.3.3. Network Slice Topology

[I-D.liu-teas-transport-network-slice-yang] specifies a YANG model for IETF Network Slice Topology.

The need for such a model is yet to be justified as the current scope is redundant with what can be already achieved using the SAP model (Section 5.3.1).

5.3.4. NRP

[I-D.wdbsp-teas-nrp-yang] specifies a YANG data model for managing NRPs.

5.3.5. Network Slice Mapping

[I-D.dhody-teas-ietf-network-slice-mapping] specifies an IETF Network Slice Service mapping YANG model. The model supports the following mappings:

6. Control Plane Extensions

6.1. BGP Classful Transport Planes

[I-D.ietf-idr-bgp-ct] specifies mechanisms for classifying underlay routes into a set of classes, called transport classes, and mapping service-specific routes to a specific transport class. For example, [I-D.ietf-idr-bgp-ct] can be used to create a customized topology for Network Slices. These topologies (transport classes) will be typically created to satisfy certain TE characteristics. A new Transport Class Route Target extended community is defined for this purpose. A transport class is identified by a 4-octet identifier: Transport Class ID.

6.2. NRP

6.2.1. BGP Flowspec

[I-D.ietf-idr-flowspec-network-slice-ts] specifies a BGP Flowspec extension for NRP traffic steering.

6.2.2. BGP-LS Filters in SR

[I-D.drake-teas-bgp-ls-filter-nrp] specifies new BGP-LS attributes, called BGP-LS Filters, for NRPs in SR networks. A BGP-LS Filter provides a description of a subset of the links and nodes in an underlay network. Ingress PE selects a path to an egress PE from the topology defined by the BGP-LS Filters it has imported for a given VPN.

6.2.3. SR Policies Extensions

6.2.3.1. BGP

[I-D.dong-idr-sr-policy-nrp] and [I-D.liu-idr-bgp-network-slicing] define extensions to BGP in order to advertise NRP ID in an SR Policy. The NRP ID is encoded in 4 octets.

6.2.3.2. BGP-LS

[I-D.chen-idr-bgp-ls-sr-policy-nrp] specifies SR Policy extensions for NRP in BGP-LS. The NRP ID is encoded in 4 octets.

6.2.4. PCEP Extensions

[I-D.dong-pce-pcep-nrp] specifie Path Computation Element Communication Protocol (PCEP) extensions for NRP. The NRP ID is encoded in 4 octets.

6.3. Virtual Transport Networks (VTNs)

6.3.1. IS-IS MT

[I-D.ietf-lsr-isis-sr-vtn-mt] specifies how to use IS-IS Multi-Topology (MT) for SR-based VTNs.

6.3.2. BGP-LS

[I-D.ietf-idr-bgpls-sr-vtn-mt] describes a mechanism to distribute the information of SR-based VTNs to the network controller using BGP-LS with Multi-Topology.

7. Data Plane Extensions

7.1. Slice Identifier in the MPLS Entropy Label

[I-D.decraene-mpls-slid-encoded-entropy-label-id] proposes an approach to encode slice identifiers in a portion of the MPLS Entropy Label (EL). The number of bits to be used for encoding the slice identifier in the EL is policy-based. Transit LSRs uses the slice identifier in the EL to apply per-slice policies.

7.2. Slice Identifier in IPv6 Flow Label

[I-D.filsfils-spring-srv6-stateless-slice-id] proposes to encode slice identifers in a portion of the IPv6 Flow Label. Slice identifiers are used by intermediate IPv6 routers to process the packet according to a network slice policy.

7.3. Slice Identifier in the Source Address of Encapsulated SRH

When an ingress SR router encapsulates a packet in an IPv6 packet with an SRH, [I-D.cheng-spring-srv6-encoding-network-sliceid] suggests to use the least significant bits of the outer IPv6 source address to encode a slide identifier. SLID Presence Indicator (SPI) is used to indicate the presence of a slice identifier. The number of bits used to encode slice identifiers is local to an SR domain.

7.4. VTN Resource ID in an IPv6 Extension Header

[I-D.ietf-6man-enhanced-vpn-vtn-id] describes a mechanism to carry an identifier, called VTN resource ID, in the IPv6 Hop-by-Hop extension header. The document claims that "VTN resource ID" is equivalent to NRP-ID, but does motivate why another yet ID is thus needed rather than using "NRP-ID".

The length of the VTN ID depends on the context type. When CT=0, the VTN ID is a 4-octet ID.

7.5. NRP

7.5.1. Resource-aware Segments

An NRP can be represented in SR networks using a set of NRP-specific resource-aware segments [I-D.ietf-spring-resource-aware-segments] [I-D.ietf-spring-sr-for-enhanced-vpn].

7.5.2. NRP ID in SRv6

[I-D.liu-spring-nrp-id-in-srv6-segment] specifies an approach to encode the NRP ID in the SRH. This ID is used by intermediate IPv6 routers to identify the NRP to be used for forwarding. The encoding of the NRP ID in an IPv6 address is variable; an instruction is thus needed to help identifyint the NRP-ID position (e.g., low 16 bits).

7.5.3. NRP Selector in MPLS Network Actions

As mentioned in Section 3.2, packets that are associated with a Slice-Flow Aggregate may carry an NRP Selector (NRPS). This selector is intended to be conveyed in the packet's network layer header to identify the flow aggregate to which a packet belongs. [I-D.li-mpls-mna-nrp-selector] investigates a set of options to use MPLS Network Actions (MNA) to carry the NRPS:

  • 13-bit NRP Selector (NRPS13) Action
  • 20-bit NRP Selector (NRPS20) Action
  • 20-bit Entropy and NRP Selector (ENRPS20) Action

8. OAM

8.1. LSP Ping/Traceroute Extensions

[I-D.liu-mpls-lsp-ping-nrp] specifies extenstions to the LSP Ping/Traceroute to convey NRP-ID in SR domains.

The NRP-ID is a encoded as a 4-octet field.

8.2. Precision Availability Metrics for SLO-Governed End-to-End Services

[I-D.ietf-ippm-pam] introduces a new set of metrics, called Precision Availability Metrics (PAM). These metrics are used to assess whether a service (e.g., Network Slice service) is provided in compliance with its specified SLOs.

9. Misc

9.1. Scalability Considerations for NRP

[I-D.ietf-teas-nrp-scalability] discusses a set of scenarios for the deployment of NRP with a focus on scalability implications. The document reasons about the increase of requested IETF Network Slice services that would require NRPs. Such an increase of slices is speculative at this stage.

10. Security Considerations

Security considerations of the mechanisms listed in the document are discussed in the relevant documents that specify these mechanisms.

11. IANA Considerations

This document does not make any request to IANA.

12. Informative References

[I-D.barguil-teas-network-slices-instantation]
Barguil, S., Contreras, L. M., Lopez, V., Rokui, R., de Dios, O. G., and D. King, "Instantiation of IETF Network Slices in Service Providers Network", Work in Progress, Internet-Draft, draft-barguil-teas-network-slices-instantation-06, , <https://datatracker.ietf.org/doc/html/draft-barguil-teas-network-slices-instantation-06>.
[I-D.boro-opsawg-ntw-attachment-circuit]
Boucadair, M., Roberts, R., de Dios, O. G., Barguil, S., and B. Wu, "A Network YANG Data Model for Attachment Circuits", Work in Progress, Internet-Draft, draft-boro-opsawg-ntw-attachment-circuit-02, , <https://datatracker.ietf.org/doc/html/draft-boro-opsawg-ntw-attachment-circuit-02>.
[I-D.boro-opsawg-teas-attachment-circuit]
Boucadair, M., Roberts, R., de Dios, O. G., Barguil, S., and B. Wu, "YANG Data Models for 'Attachment Circuits'-as-a-Service (ACaaS)", Work in Progress, Internet-Draft, draft-boro-opsawg-teas-attachment-circuit-06, , <https://datatracker.ietf.org/doc/html/draft-boro-opsawg-teas-attachment-circuit-06>.
[I-D.boro-opsawg-teas-common-ac]
Boucadair, M., Roberts, R., de Dios, O. G., Barguil, S., and B. Wu, "A Common YANG Data Model for Attachment Circuits", Work in Progress, Internet-Draft, draft-boro-opsawg-teas-common-ac-02, , <https://datatracker.ietf.org/doc/html/draft-boro-opsawg-teas-common-ac-02>.
[I-D.chen-idr-bgp-ls-sr-policy-nrp]
Chen, R., Zhao, D., Gong, L., and Y. Zhu, "SR Policies Extensions for NRP in BGP-LS", Work in Progress, Internet-Draft, draft-chen-idr-bgp-ls-sr-policy-nrp-02, , <https://datatracker.ietf.org/doc/html/draft-chen-idr-bgp-ls-sr-policy-nrp-02>.
[I-D.cheng-spring-srv6-encoding-network-sliceid]
Cheng, W., Yang, G., Lin, C., Gong, L., Zadok, S., Wu, M., and X. wang, "Encoding Network Slice Identification for SRv6", Work in Progress, Internet-Draft, draft-cheng-spring-srv6-encoding-network-sliceid-06, , <https://datatracker.ietf.org/doc/html/draft-cheng-spring-srv6-encoding-network-sliceid-06>.
[I-D.contreras-teas-slice-controller-models]
Contreras, L. M., Rokui, R., Tantsura, J., Wu, B., Liu, X., Dhody, D., and S. Belotti, "IETF Network Slice Controller and its associated data models", Work in Progress, Internet-Draft, draft-contreras-teas-slice-controller-models-05, , <https://datatracker.ietf.org/doc/html/draft-contreras-teas-slice-controller-models-05>.
[I-D.decraene-mpls-slid-encoded-entropy-label-id]
Decraene, B., Filsfils, C., Henderickx, W., Saad, T., Beeram, V. P., and L. Jalil, "Using Entropy Label for Network Slice Identification in MPLS networks.", Work in Progress, Internet-Draft, draft-decraene-mpls-slid-encoded-entropy-label-id-05, , <https://datatracker.ietf.org/doc/html/draft-decraene-mpls-slid-encoded-entropy-label-id-05>.
[I-D.dhody-teas-ietf-network-slice-mapping]
Dhody, D. and B. Wu, "IETF Network Slice Service Mapping YANG Model", Work in Progress, Internet-Draft, draft-dhody-teas-ietf-network-slice-mapping-03, , <https://datatracker.ietf.org/doc/html/draft-dhody-teas-ietf-network-slice-mapping-03>.
[I-D.dong-idr-sr-policy-nrp]
Dong, J., Hu, Z., and R. Pang, "BGP SR Policy Extensions for Network Resource Partition", Work in Progress, Internet-Draft, draft-dong-idr-sr-policy-nrp-02, , <https://datatracker.ietf.org/doc/html/draft-dong-idr-sr-policy-nrp-02>.
[I-D.dong-pce-pcep-nrp]
Dong, J., Fang, S., Xiong, Q., Peng, S., Han, L., Wang, M., Beeram, V. P., and T. Saad, "Path Computation Element Communication Protocol (PCEP) Extensions for Network Resource Partition (NRP)", Work in Progress, Internet-Draft, draft-dong-pce-pcep-nrp-00, , <https://datatracker.ietf.org/doc/html/draft-dong-pce-pcep-nrp-00>.
[I-D.drake-teas-bgp-ls-filter-nrp]
Drake, J., Farrel, A., Jalil, L., and A. Lingala, "Using BGP-LS Filters to Instanted Network Resource Partitions", Work in Progress, Internet-Draft, draft-drake-teas-bgp-ls-filter-nrp-00, , <https://datatracker.ietf.org/doc/html/draft-drake-teas-bgp-ls-filter-nrp-00>.
[I-D.filsfils-spring-srv6-stateless-slice-id]
Filsfils, C., Clad, F., Camarillo, P., Raza, S., Voyer, D., and R. Rokui, "Stateless and Scalable Network Slice Identification for SRv6", Work in Progress, Internet-Draft, draft-filsfils-spring-srv6-stateless-slice-id-07, , <https://datatracker.ietf.org/doc/html/draft-filsfils-spring-srv6-stateless-slice-id-07>.
[I-D.gong-teas-hierarchical-slice-solution]
Gong, L., Cheng, W., Lin, C., Chen, M., Dong, J., Chen, R., and Y. Liang, "Segment Routing based Solution for Hierarchical IETF Network Slices", Work in Progress, Internet-Draft, draft-gong-teas-hierarchical-slice-solution-01, , <https://datatracker.ietf.org/doc/html/draft-gong-teas-hierarchical-slice-solution-01>.
[I-D.ietf-6man-enhanced-vpn-vtn-id]
Dong, J., Li, Z., Xie, C., Ma, C., and G. S. Mishra, "Carrying Virtual Transport Network (VTN) Information in IPv6 Extension Header", Work in Progress, Internet-Draft, draft-ietf-6man-enhanced-vpn-vtn-id-04, , <https://datatracker.ietf.org/doc/html/draft-ietf-6man-enhanced-vpn-vtn-id-04>.
[I-D.ietf-ccamp-yang-otn-slicing]
Guo, A., Contreras, L. M., Belotti, S., Rokui, R., Xu, Y., Zhao, Y., and X. Liu, "Framework and Data Model for OTN Network Slicing", Work in Progress, Internet-Draft, draft-ietf-ccamp-yang-otn-slicing-04, , <https://datatracker.ietf.org/doc/html/draft-ietf-ccamp-yang-otn-slicing-04>.
[I-D.ietf-dmm-tn-aware-mobility]
Chunduri, U., Kaippallimalil, J., Bhaskaran, S., Tantsura, J., and P. Muley, "Mobility aware Transport Network Slicing for 5G", Work in Progress, Internet-Draft, draft-ietf-dmm-tn-aware-mobility-06, , <https://datatracker.ietf.org/doc/html/draft-ietf-dmm-tn-aware-mobility-06>.
[I-D.ietf-idr-bgp-ct]
Vairavakkalai, K. and N. Venkataraman, "BGP Classful Transport Planes", Work in Progress, Internet-Draft, draft-ietf-idr-bgp-ct-04, , <https://datatracker.ietf.org/doc/html/draft-ietf-idr-bgp-ct-04>.
[I-D.ietf-idr-bgpls-sr-vtn-mt]
Xie, C., Li, C., Dong, J., and Z. Li, "BGP-LS with Multi-topology for Segment Routing based Virtual Transport Networks", Work in Progress, Internet-Draft, draft-ietf-idr-bgpls-sr-vtn-mt-02, , <https://datatracker.ietf.org/doc/html/draft-ietf-idr-bgpls-sr-vtn-mt-02>.
[I-D.ietf-idr-flowspec-network-slice-ts]
Dong, J., Chen, R., Wang, S., and J. Wenying, "BGP Flowspec for IETF Network Slice Traffic Steering", Work in Progress, Internet-Draft, draft-ietf-idr-flowspec-network-slice-ts-00, , <https://datatracker.ietf.org/doc/html/draft-ietf-idr-flowspec-network-slice-ts-00>.
[I-D.ietf-ippm-pam]
Mirsky, G., Halpern, J. M., Min, X., Clemm, A., Strassner, J., and J. François, "Precision Availability Metrics for SLO-Governed End-to-End Services", Work in Progress, Internet-Draft, draft-ietf-ippm-pam-01, , <https://datatracker.ietf.org/doc/html/draft-ietf-ippm-pam-01>.
[I-D.ietf-lsr-isis-sr-vtn-mt]
Xie, C., Ma, C., Dong, J., and Z. Li, "Using IS-IS Multi-Topology (MT) for Segment Routing based Virtual Transport Network", Work in Progress, Internet-Draft, draft-ietf-lsr-isis-sr-vtn-mt-04, , <https://datatracker.ietf.org/doc/html/draft-ietf-lsr-isis-sr-vtn-mt-04>.
[I-D.ietf-opsawg-sap]
Boucadair, M., de Dios, O. G., Barguil, S., Wu, Q., and V. Lopez, "A YANG Network Model for Service Attachment Points (SAPs)", Work in Progress, Internet-Draft, draft-ietf-opsawg-sap-15, , <https://datatracker.ietf.org/doc/html/draft-ietf-opsawg-sap-15>.
[I-D.ietf-spring-resource-aware-segments]
Dong, J., Bryant, S., Miyasaka, T., Zhu, Y., Qin, F., Li, Z., and F. Clad, "Introducing Resource Awareness to SR Segments", Work in Progress, Internet-Draft, draft-ietf-spring-resource-aware-segments-07, , <https://datatracker.ietf.org/doc/html/draft-ietf-spring-resource-aware-segments-07>.
[I-D.ietf-spring-sr-for-enhanced-vpn]
Dong, J., Bryant, S., Miyasaka, T., Zhu, Y., Qin, F., Li, Z., and F. Clad, "Segment Routing based Virtual Transport Network (VTN) for Enhanced VPN", Work in Progress, Internet-Draft, draft-ietf-spring-sr-for-enhanced-vpn-05, , <https://datatracker.ietf.org/doc/html/draft-ietf-spring-sr-for-enhanced-vpn-05>.
[I-D.ietf-teas-5g-network-slice-application]
Geng, X., Contreras, L. M., Rokui, R., Dong, J., and I. Bykov, "IETF Network Slice Application in 3GPP 5G End-to-End Network Slice", Work in Progress, Internet-Draft, draft-ietf-teas-5g-network-slice-application-00, , <https://datatracker.ietf.org/doc/html/draft-ietf-teas-5g-network-slice-application-00>.
[I-D.ietf-teas-applicability-actn-slicing]
King, D., Drake, J., Zheng, H., and A. Farrel, "Applicability of Abstraction and Control of Traffic Engineered Networks (ACTN) to Network Slicing", Work in Progress, Internet-Draft, draft-ietf-teas-applicability-actn-slicing-03, , <https://datatracker.ietf.org/doc/html/draft-ietf-teas-applicability-actn-slicing-03>.
[I-D.ietf-teas-enhanced-vpn]
Dong, J., Bryant, S., Li, Z., Miyasaka, T., and Y. Lee, "A Framework for Enhanced Virtual Private Network (VPN+)", Work in Progress, Internet-Draft, draft-ietf-teas-enhanced-vpn-12, , <https://datatracker.ietf.org/doc/html/draft-ietf-teas-enhanced-vpn-12>.
[I-D.ietf-teas-ietf-network-slice-nbi-yang]
Wu, B., Dhody, D., Rokui, R., Saad, T., Han, L., and J. Mullooly, "A YANG Data Model for the IETF Network Slice Service", Work in Progress, Internet-Draft, draft-ietf-teas-ietf-network-slice-nbi-yang-04, , <https://datatracker.ietf.org/doc/html/draft-ietf-teas-ietf-network-slice-nbi-yang-04>.
[I-D.ietf-teas-ietf-network-slices]
Farrel, A., Drake, J., Rokui, R., Homma, S., Makhijani, K., Contreras, L. M., and J. Tantsura, "A Framework for IETF Network Slices", Work in Progress, Internet-Draft, draft-ietf-teas-ietf-network-slices-19, , <https://datatracker.ietf.org/doc/html/draft-ietf-teas-ietf-network-slices-19>.
[I-D.ietf-teas-nrp-scalability]
Dong, J., Li, Z., Gong, L., Yang, G., Guichard, J., Mishra, G. S., Qin, F., Saad, T., and V. P. Beeram, "Scalability Considerations for Network Resource Partition", Work in Progress, Internet-Draft, draft-ietf-teas-nrp-scalability-02, , <https://datatracker.ietf.org/doc/html/draft-ietf-teas-nrp-scalability-02>.
[I-D.ietf-teas-ns-ip-mpls]
Saad, T., Beeram, V. P., Dong, J., Wen, B., Ceccarelli, D., Halpern, J. M., Peng, S., Chen, R., Liu, X., Contreras, L. M., Rokui, R., and L. Jalil, "Realizing Network Slices in IP/MPLS Networks", Work in Progress, Internet-Draft, draft-ietf-teas-ns-ip-mpls-02, , <https://datatracker.ietf.org/doc/html/draft-ietf-teas-ns-ip-mpls-02>.
[I-D.ietf-teas-te-service-mapping-yang]
Lee, Y., Dhody, D., Fioccola, G., Wu, Q., Ceccarelli, D., and J. Tantsura, "Traffic Engineering (TE) and Service Mapping YANG Data Model", Work in Progress, Internet-Draft, draft-ietf-teas-te-service-mapping-yang-13, , <https://datatracker.ietf.org/doc/html/draft-ietf-teas-te-service-mapping-yang-13>.
[I-D.li-mpls-mna-nrp-selector]
Li, T., Drake, J., Beeram, V. P., Saad, T., and I. Meilik, "MPLS Network Actions for Network Resource Partition Selector", Work in Progress, Internet-Draft, draft-li-mpls-mna-nrp-selector-00, , <https://datatracker.ietf.org/doc/html/draft-li-mpls-mna-nrp-selector-00>.
[I-D.li-teas-composite-network-slices]
Li, Z., Dong, J., Pang, R., Zhu, Y., and L. M. Contreras, "Realization of Composite IETF Network Slices", Work in Progress, Internet-Draft, draft-li-teas-composite-network-slices-00, , <https://datatracker.ietf.org/doc/html/draft-li-teas-composite-network-slices-00>.
[I-D.liu-idr-bgp-network-slicing]
Yao, L. and S. Peng, "BGP Extensions to Support Packet Network Slicing in SR Policy", Work in Progress, Internet-Draft, draft-liu-idr-bgp-network-slicing-02, , <https://datatracker.ietf.org/doc/html/draft-liu-idr-bgp-network-slicing-02>.
[I-D.liu-mpls-lsp-ping-nrp]
Yao, L. and S. Peng, "LSP Ping/Traceroute for SR-MPLS NRP SIDs", Work in Progress, Internet-Draft, draft-liu-mpls-lsp-ping-nrp-01, , <https://datatracker.ietf.org/doc/html/draft-liu-mpls-lsp-ping-nrp-01>.
[I-D.liu-spring-nrp-id-in-srv6-segment]
Liu, Y., Lin, C., Li, H., and L. Gong, "NRP ID in SRv6 segment", Work in Progress, Internet-Draft, draft-liu-spring-nrp-id-in-srv6-segment-02, , <https://datatracker.ietf.org/doc/html/draft-liu-spring-nrp-id-in-srv6-segment-02>.
[I-D.liu-teas-transport-network-slice-yang]
Liu, X., Tantsura, J., Bryskin, I., Contreras, L. M., Wu, Q., Belotti, S., Rokui, R., Guo, A., and I. Busi, "IETF Network Slice Topology YANG Data Model", Work in Progress, Internet-Draft, draft-liu-teas-transport-network-slice-yang-06, , <https://datatracker.ietf.org/doc/html/draft-liu-teas-transport-network-slice-yang-06>.
[I-D.srld-teas-5g-slicing]
Szarkowicz, K. G., Roberts, R., Lucek, J., Boucadair, M., and L. M. Contreras, "A Realization of IETF Network Slices for 5G Networks Using Current IP/ MPLS Technologies", Work in Progress, Internet-Draft, draft-srld-teas-5g-slicing-09, , <https://datatracker.ietf.org/doc/html/draft-srld-teas-5g-slicing-09>.
[I-D.sw-detnet-network-slice-mapping-yang]
Song, X. and H. Wu, "YANG Data Model for DetNet Mapping with Network Slice", Work in Progress, Internet-Draft, draft-sw-detnet-network-slice-mapping-yang-02, , <https://datatracker.ietf.org/doc/html/draft-sw-detnet-network-slice-mapping-yang-02>.
[I-D.wdbsp-teas-nrp-yang]
Wu, B., Dhody, D., Beeram, V. P., Saad, T., and S. Peng, "A YANG Data Model for Network Resource Partitions (NRPs)", Work in Progress, Internet-Draft, draft-wdbsp-teas-nrp-yang-00, , <https://datatracker.ietf.org/doc/html/draft-wdbsp-teas-nrp-yang-00>.
[RFC9181]
Barguil, S., Gonzalez de Dios, O., Ed., Boucadair, M., Ed., and Q. Wu, "A Common YANG Data Model for Layer 2 and Layer 3 VPNs", RFC 9181, DOI 10.17487/RFC9181, , <https://www.rfc-editor.org/rfc/rfc9181>.
[RFC9182]
Barguil, S., Gonzalez de Dios, O., Ed., Boucadair, M., Ed., Munoz, L., and A. Aguado, "A YANG Network Data Model for Layer 3 VPNs", RFC 9182, DOI 10.17487/RFC9182, , <https://www.rfc-editor.org/rfc/rfc9182>.
[RFC9291]
Boucadair, M., Ed., Gonzalez de Dios, O., Ed., Barguil, S., and L. Munoz, "A YANG Network Data Model for Layer 2 VPNs", RFC 9291, DOI 10.17487/RFC9291, , <https://www.rfc-editor.org/rfc/rfc9291>.

Acknowledgments

Thanks to Kaliraj Vairavakkalai for the comments.

Author's Address

Mohamed Boucadair
Orange
35000 Rennes
France