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Versions: 00                                                            
LSR Working Group                                                T. Saad
Internet-Draft                                                 V. Beeram
Intended status: Standards Track                        Juniper Networks
Expires: August 26, 2021                                         R. Chen
                                                                 S. Peng
                                                         ZTE Corporation
                                                                  B. Wen
                                                                 Comcast
                                                           D. Ceccarelli
                                                                Ericsson
                                                       February 22, 2021


               IGP Extensions for SR Slice Aggregate SIDs
                     draft-bestbar-lsr-spring-sa-00

Abstract

   Segment Routing (SR) defines a set of topological "segments" within
   an IGP topology to enable steering over a specific SR path.  These
   segments are advertised by the link-state routing protocols (IS-IS
   and OSPF).

   This document describes extensions to the IS-IS that enable
   advertising Slice Aggregate SR segments that share the same IGP
   computed forwarding path but offer a forwarding treatment (e.g.
   scheduling and drop policy) that is associated with a specific Slice
   Aggregate.

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 August 26, 2021.






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Copyright Notice

   Copyright (c) 2021 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (https://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
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   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.  Requirements Language . . . . . . . . . . . . . . . . . . . .   3
   3.  Slice Aggregate SIDs for SR-MPLS  . . . . . . . . . . . . . .   3
     3.1.  IS-IS Slice Aggregate Prefix-SID Sub-TLV  . . . . . . . .   3
     3.2.  IS-IS Slice Aggregate Adjacency-SID Sub-TLV . . . . . . .   5
     3.3.  IS-IS Slice Aggregate LAN Adjacency-SIDs  . . . . . . . .   6
   4.  Slice Aggregate SIDs for SRv6 . . . . . . . . . . . . . . . .   7
     4.1.  SRv6 SID Slice Aggregate Sub-Sub-TLV  . . . . . . . . . .   7
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   8
     5.1.  SR Slice Aggregate Prefix-SID sub-TLV . . . . . . . . . .   9
     5.2.  SR Slice Aggregate Adjacency-SID sub-TLV  . . . . . . . .   9
     5.3.  SR Slice Aggregate LAN-Adj-SID sub-TLV  . . . . . . . . .   9
     5.4.  SRv6 SID Slice Aggregate Sub-Sub-TLV  . . . . . . . . . .   9
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .   9
   7.  Acknowledgement . . . . . . . . . . . . . . . . . . . . . . .   9
   8.  Contributors  . . . . . . . . . . . . . . . . . . . . . . . .   9
   9.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  10
     9.1.  Normative References  . . . . . . . . . . . . . . . . . .  10
     9.2.  Informative References  . . . . . . . . . . . . . . . . .  11
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  12

1.  Introduction

   The Segment Routing (SR) architecture [RFC8402] defines a set of
   topological "segments" within an IGP topology as means to enable
   steering over a specific SR end-to-end path.  These segments are
   advertised by the IGP link-state routing protocols (IS-IS and OSPF).
   The SR control plane can be applied to both IPv6 and MPLS data
   planes.





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   The definition of a network slice for use within the IETF and the
   characteristics of IETF network slice are specified in
   [I-D.ietf-teas-ietf-network-slice-definition].  A framework for
   reusing IETF VPN and traffic-engineering technologies to realize IETF
   network slices is discussed in [I-D.nsdt-teas-ns-framework].

   [I-D.bestbar-teas-ns-packet] introduces the notion of a Slice
   Aggregate as the construct that comprises of one of more IETF network
   slice traffic streams.  A slice policy can be used to realize a slice
   aggregate by instantiating specific control and data plane resources
   on select topological elements in an IP/MPLS network.

   [I-D.bestbar-spring-scalable-ns] describes an approach to extend SR
   to advertiser new SID types called Slice Aggregate (SA) SIDs.  Such
   SA SIDs are used on a router to define the forwarding action for a
   packet (next-hop selection), as well as enforce the specific
   treatment (scheduling and drop policy) associated with the Slice
   Aggregate.

   This document defines the IS-IS and OSPF encodings for the IGP-Prefix
   Segment, the IGP-Adjacency Segment, the IGP-LAN-Adjacency Segment
   that are required to support the signaling of SR Slice Aggregate SIDs
   operating over SR-MPLS and SRv6 dataplanes.  When the Slice Aggregate
   segments have the same topology (and Algorithm for Prefix-SIDs), the
   SA SIDs share the same forwarding path (IGP next-hop(s)), but are
   associated with different forwarding treatment (e.g. scheduling and
   drop policy) that is associated with the specific Slice Aggregate.

2.  Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in BCP
   14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

3.  Slice Aggregate SIDs for SR-MPLS

   Segment Routing can be directly instantiated on the MPLS data plane
   through the use of the Segment Routing header instantiated as a stack
   of MPLS labels defined in [RFC8402].

3.1.  IS-IS Slice Aggregate Prefix-SID Sub-TLV

   [RFC8667] defines the IS-IS Prefix Segment Identifier sub-TLV
   (Prefix-SID sub-TLV) that is applicable to SR-MPLS dataplane.  The
   Prefix-SID sub-TLV carries the Segment Routing IGP-Prefix-SID, and is
   associated with a prefix advertised by a router.



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   A new IS-IS SR Slice Aggregate Prefix-SID (SA Prefix-SID) sub-TLV is
   defined to allow a router advertising a prefix to associate multiple
   SA Prefix-SIDs to the same prefix.  The SA Prefix-SIDs associated
   with the same prefix share the same IGP path to the destination
   prefix within the specific mapped or customized topology/algorithm
   but offer the specific QoS treatment associated with the specific
   Slice Aggregate.

   The Slice Aggregate ID is carried in the SA Prefix-SID sub-TLV to
   associate it to Prefix-SID with a specific Slice Aggregate.  The SA
   Prefix-SID sub-TLV has the following format:

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |   Type=TBD1   |    Length     |     Flag      |   Algorithm   |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                              SA-ID                            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                      SID/Index/Label(Variable)                |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


               Figure 1: SA Prefix-SID sub-TLV for SR-MPLS.

   where:

      Type: TBD1 (Suggested value to be assigned by IANA)

      Length: Variable.  Depending on the size of the SID.

      The "Flags" and "SID/Index/Label" fields are the same as the
      Prefix-SID sub-TLV [RFC8667].

      Algorithm: 1 octet.  Associated algorithm.  Algorithm values are
      defined in the IGP Algorithm Type registry

      SA-ID: Identifies a specific Slice Aggregate within the IGP
      domain.

   This sub-TLV MAY be present in any of the following TLVs:

      TLV-135 (Extended IPv4 reachability) defined in [RFC5305].

      TLV-235 (Multitopology IPv4 Reachability) defined in [RFC5120].

      TLV-236 (IPv6 IP Reachability) defined in [RFC5308].




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      TLV-237 (Multitopology IPv6 IP Reachability) defined in [RFC5120].

   This sub-TLV MAY appear multiple times in each TLV.

3.2.  IS-IS Slice Aggregate Adjacency-SID Sub-TLV

   [RFC8667] defines the IS-IS Adjacency Segment Identifier sub-TLV
   (Adj-SID sub-TLV).  The Adj-SID sub-TLV is an optional sub-TLV
   carrying the Segment Routing IGP Adjacency-SID as defined in
   [RFC8402].

   A new SR Slice Aggregate Adjacency-SID (SA Adj-SID) sub-TLV is
   defined to allow a router to allocate and advertise multiple SA Adj-
   SIDs towards the same IS-IS neighbor (adjacency).  The SA Adj-SIDs
   allows a router to enforce the specific treatment associated with the
   Slice Aggregate.

   The Slice Aggregate ID is carried in the SA Adj-SID sub-TLV to
   associate it to the specific Slice Aggregate.  The SA Adj-SID sub-TLV
   has the following format:

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |   Type        |     Length    |     Flags     |     Weight    |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                            SA-ID                              |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                      SID/Index/Label(Variable)                |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                 Figure 2: SA Adj-SID sub-TLV for SR-MPLS.

   where:

      Type: TBD2 (Suggested value to be assigned by IANA)

      Length: Variable.  Depending on the size of the SID.

      The "Flags" and "SID/Index/Label" fields are the same as the Adj-
      SID sub-TLV [RFC8667].

      SA-ID: Identifies a specific Slice Aggregate within the IGP
      domain.

   This sub-TLV MAY be present in any of the following TLVs:

      TLV-22 (Extended IS reachability) [RFC5305].



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      TLV-222 (Multitopology IS) [RFC5120].

      TLV-23 (IS Neighbor Attribute) [RFC5311].

      TLV-223 (Multitopology IS Neighbor Attribute) [RFC5311].

      TLV-141 (inter-AS reachability information) [RFC5316].

   Multiple Adj-SID sub-TLVs MAY be associated with a single IS-IS
   neighbor.  This sub-TLV MAY appear multiple times in each TLV.

3.3.  IS-IS Slice Aggregate LAN Adjacency-SIDs

   In LAN subnetworks, [RFC8667] defines the SR-MPLS LAN-Adj-SID sub-TLV
   for a router to advertise the Adj-SID of each of its neighbors.

   A new SR Slice Aggregate LAN Adjacency-SID (SA LAN-Adj-SID) sub-TLV
   is defined to allow a router to allocate and advertise multiple SA
   LAN-Adj-SIDs towards each of its neighbors on the LAN.  The SA LAN-
   Adj-SIDs allows a router to enforce the specific treatment associated
   with the specific Slice Aggregate towards a neighbor.

   The Slice Aggregate ID is carried in the SA LAN-Adj-SID sub-TLV to
   associate it to the specific Slice Aggregate.  The SA LAN-Adj-SID
   sub-TLV has the following format:

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |   Type=TBD3   |     Length    |      Flags    |    Weight     |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                            SA-ID                              |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                  Neighbor System-ID (ID length octets)        |
      +                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                   SID/Label/Index (variable)                  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

               Figure 3: SA LAN Adj-SID sub-TLV for SR-MPLS.

   where:




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      Type: TBD3 (Suggested value to be assigned by IANA)

      Length: Variable.  Depending on the size of the SID.

      The "Flags" and "SID/Index/Label" fields are the same as the LAN-
      Adj-SID sub-TLV [RFC8667].

      SA-ID: Identifies a specific Slice Aggregate within the IGP
      domain.

   This sub-TLV MAY be present in any of the following TLVs:

      TLV-22 (Extended IS reachability) [RFC5305].

      TLV-222 (Multitopology IS) [RFC5120].

      TLV-23 (IS Neighbor Attribute) [RFC5311].

      TLV-223 (Multitopology IS Neighbor Attribute) [RFC5311].

   Multiple LAN-Adj-SID sub-TLVs MAY be associated with a single IS-IS
   neighbor.  This sub-TLV MAY appear multiple times in each TLV.

      Editor Note: the OSPF Sub-TLV sections will be populated in
      further update.

4.  Slice Aggregate SIDs for SRv6

   Segment Routing can be directly instantiated on the IPv6 data plane
   through the use of the Segment Routing Header defined in [RFC8754].
   SRv6 refers to this SR instantiation on the IPv6 dataplane.

   The SRv6 Locator TLV was introduced in
   [I-D.ietf-lsr-isis-srv6-extensions] to advertise SRv6 Locators and
   End SIDs associated with each locator.

4.1.  SRv6 SID Slice Aggregate Sub-Sub-TLV

   The SRv6 End SID sub-TLV was introduced in
   [I-D.ietf-lsr-isis-srv6-extensions] to advertise SRv6 Segment
   Identifiers (SID) with Endpoint behaviors which do not require a
   particular neighbor.

   The SRv6 End SID sub-TLV is advertised in the SRv6 Locator TLV, and
   inherits the topology/algorithm from the parent locator.  The SRv6
   End SID sub-TLV defined in [I-D.ietf-lsr-isis-srv6-extensions]
   carries optional sub-sub-TLVs.




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   A new SRv6 Slice Aggregate (SA) SID Sub-Sub-TLV is defined to allow a
   router to assign and advertise an SRv6 End SID that is associated
   with a specific Slice Aggregate.  The SRv6 SID SA Sub-Sub-TLV allows
   routers to infer and enforce the specific treatment associated with
   the Slice Aggregate on the selected next-hops along the path to the
   End SID destination.

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |   Type=TBD4   |     Length    |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                            SA-ID                              |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

            Figure 4: SRv6 SID SA Sub-Sub-TLV format for SRv6.

   where:

      Type: TBD4

      Length: 4 octets.

      SA-ID: Identifies a specific Slice Aggregate within the IGP
      domain.

   ISIS SRv6 SID SA Sub-Sub-TLV MUST NOT appear more than once in its
   parent Sub-TLV.  If it appears more than once in its parent Sub- TLV,
   the parent Sub-TLV MUST be ignored by the receiver.

   The new SRv6 SID SA Sub-Sub-TLV is an optional Sub-Sub-TLV of:

      SRv6 End SID Sub-TLV (Section 7.2 of
      [I-D.ietf-lsr-isis-srv6-extensions])

      SRv6 End.X SID Sub-TLV (Section 8.1 of
      [I-D.ietf-lsr-isis-srv6-extensions])

      SRv6 LAN End.X SID Sub-TLV (Section 8.2 of
      [I-D.ietf-lsr-isis-srv6-extensions])

5.  IANA Considerations

   This document requests allocation for the following Sub-TLVs.







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5.1.  SR Slice Aggregate Prefix-SID sub-TLV

   This TLV shares sub-TLV space with existing "Sub-TLVs for TLVs
   135,235,226 and 237 registry".

      Type: TBD1 (to be assigned by IANA).

5.2.  SR Slice Aggregate Adjacency-SID sub-TLV

   This TLV shares sub-TLV space with existing "Sub-TLVs for TLVs 22,
   222, 23, 223 and 141 registry".

      Type: TBD2 (to be assigned by IANA).

5.3.  SR Slice Aggregate LAN-Adj-SID sub-TLV

   This TLV shares sub-TLV space with existing "Sub-TLVs for TLVs 22,
   222, 23, and 223 registry".

      Type: TBD3 (to be assigned by IANA).

5.4.  SRv6 SID Slice Aggregate Sub-Sub-TLV

      Type: TBD4 (to be assigned by IANA).

6.  Security Considerations

   TBD.

7.  Acknowledgement

   The authors would like to thank Swamy SRK, and Prabhu Raj Villadathu
   Karunakaran for their review of this document, and for providing
   valuable feedback on it.

8.  Contributors

   The following individuals contributed to this document:













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      Colby Barth
      Juniper Networks
      Email: cbarth@juniper.net

      Srihari R.  Sangli
      Juniper Networks
      Email: ssangli@juniper.net

      Chandra Ramachandran
      Juniper Networks
      Email: csekar@juniper.net

9.  References

9.1.  Normative References

   [I-D.bestbar-spring-scalable-ns]
              Saad, T. and V. Beeram, "Scalable Network Slicing over SR
              Networks", draft-bestbar-spring-scalable-ns-00 (work in
              progress), December 2020.

   [I-D.bestbar-teas-ns-packet]
              Saad, T., Beeram, V., Wen, B., Ceccarelli, D., Halpern,
              J., Peng, S., Chen, R., and X. Liu, "Realizing Network
              Slices in IP/MPLS Networks", draft-bestbar-teas-ns-
              packet-01 (work in progress), December 2020.

   [I-D.ietf-lsr-isis-srv6-extensions]
              Psenak, P., Filsfils, C., Bashandy, A., Decraene, B., and
              Z. Hu, "IS-IS Extension to Support Segment Routing over
              IPv6 Dataplane", draft-ietf-lsr-isis-srv6-extensions-11
              (work in progress), October 2020.

   [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>.

   [RFC5120]  Przygienda, T., Shen, N., and N. Sheth, "M-ISIS: Multi
              Topology (MT) Routing in Intermediate System to
              Intermediate Systems (IS-ISs)", RFC 5120,
              DOI 10.17487/RFC5120, February 2008,
              <https://www.rfc-editor.org/info/rfc5120>.

   [RFC5305]  Li, T. and H. Smit, "IS-IS Extensions for Traffic
              Engineering", RFC 5305, DOI 10.17487/RFC5305, October
              2008, <https://www.rfc-editor.org/info/rfc5305>.




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   [RFC5308]  Hopps, C., "Routing IPv6 with IS-IS", RFC 5308,
              DOI 10.17487/RFC5308, October 2008,
              <https://www.rfc-editor.org/info/rfc5308>.

   [RFC5311]  McPherson, D., Ed., Ginsberg, L., Previdi, S., and M.
              Shand, "Simplified Extension of Link State PDU (LSP) Space
              for IS-IS", RFC 5311, DOI 10.17487/RFC5311, February 2009,
              <https://www.rfc-editor.org/info/rfc5311>.

   [RFC5316]  Chen, M., Zhang, R., and X. Duan, "ISIS Extensions in
              Support of Inter-Autonomous System (AS) MPLS and GMPLS
              Traffic Engineering", RFC 5316, DOI 10.17487/RFC5316,
              December 2008, <https://www.rfc-editor.org/info/rfc5316>.

   [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>.

   [RFC8402]  Filsfils, C., Ed., Previdi, S., Ed., Ginsberg, L.,
              Decraene, B., Litkowski, S., and R. Shakir, "Segment
              Routing Architecture", RFC 8402, DOI 10.17487/RFC8402,
              July 2018, <https://www.rfc-editor.org/info/rfc8402>.

   [RFC8667]  Previdi, S., Ed., Ginsberg, L., Ed., Filsfils, C.,
              Bashandy, A., Gredler, H., and B. Decraene, "IS-IS
              Extensions for Segment Routing", RFC 8667,
              DOI 10.17487/RFC8667, December 2019,
              <https://www.rfc-editor.org/info/rfc8667>.

   [RFC8754]  Filsfils, C., Ed., Dukes, D., Ed., Previdi, S., Leddy, J.,
              Matsushima, S., and D. Voyer, "IPv6 Segment Routing Header
              (SRH)", RFC 8754, DOI 10.17487/RFC8754, March 2020,
              <https://www.rfc-editor.org/info/rfc8754>.

9.2.  Informative References

   [I-D.ietf-teas-ietf-network-slice-definition]
              Rokui, R., Homma, S., Makhijani, K., Contreras, L., and J.
              Tantsura, "Definition of IETF Network Slices", draft-ietf-
              teas-ietf-network-slice-definition-00 (work in progress),
              January 2021.

   [I-D.nsdt-teas-ns-framework]
              Gray, E. and J. Drake, "Framework for Transport Network
              Slices", draft-nsdt-teas-ns-framework-04 (work in
              progress), July 2020.





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Authors' Addresses

   Tarek Saad
   Juniper Networks

   Email: tsaad@juniper.net


   Vishnu Pavan Beeram
   Juniper Networks

   Email: vbeeram@juniper.net


   Ran Chen
   ZTE Corporation

   Email: chen.ran@zte.com.cn


   Shaofu Peng
   ZTE Corporation

   Email: peng.shaofu@zte.com.cn


   Bin Wen
   Comcast

   Email: Bin_Wen@cable.comcast.com


   Daniele Ceccarelli
   Ericsson

   Email: daniele.ceccarelli@ericsson.com















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