



DMM Working Group                                      J. Kaippallimalil
Internet-Draft                                                 Futurewei
Intended status: Standards Track                          L.M. Contreras
Expires: 9 April 2026                                         Telefonica
                                                             U. Chunduri
                                                       Intel Corporation
                                                          6 October 2025


 A YANG Data Model for Attachment Circuit as a Service with UDP Tunnel
                                Support
                   draft-jlu-dmm-udp-tunnel-acaas-01

Abstract

   Delivery of network services over a Layer 3 tunnel assumes that the
   appropriate setup is provisioned over links that connect the customer
   termination points and provider network.  The required setup to allow
   successful data exchange over these links is referred to as an
   attachment circuit (AC) while the underlying link for carrying
   network services is referred to as "bearer", in this case a Layer 3
   UDP tunnel.

   This document specifies an extension for UDP tunnel as Layer 3 bearer
   to the YANG service data model for AC.

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 9 April 2026.

Copyright Notice

   Copyright (c) 2025 IETF Trust and the persons identified as the
   document authors.  All rights reserved.




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   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 Revised BSD License text as
   described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Revised BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Attachment Circuit for UDP Tunnel . . . . . . . . . . . . . .   3
   3.  ietf-ac-udp-tunnel YANG Module  . . . . . . . . . . . . . . .   4
   4.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .   6
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .   6
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   7
   7.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   7
     7.1.  Normative References  . . . . . . . . . . . . . . . . . .   7
     7.2.  Informative References  . . . . . . . . . . . . . . . . .   8
   Appendix A.  Abbreviations  . . . . . . . . . . . . . . . . . . .   9
   Appendix B.  Example  . . . . . . . . . . . . . . . . . . . . . .  10
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  16

1.  Introduction

   Connectivity services provided by networks to customers ensure the
   transfer of data between termination points via a provider network.
   The objectives of the connectivity service can be negotiated and
   agreed between customers and network providers.  To facilitate data
   transfer within the provider network, it is assumed that the
   appropriate setup is provisioned over links that connect customer
   termination points and provider network (usually via Provider Edges
   (PEs)).  This is referred to as attachment circuit (AC) and the
   underlying link defined in this document is a UDP tunnel as Layer 3
   bearer.  In general, a bearer can be described as a physical or
   logical link that connects a customer node (or site) to a provider
   network.  [I-D.ietf-opsawg-teas-attachment-circuit] describes further
   details of bearers and 'Attachment Circuits'-as-a-service.

   [I-D.ietf-opsawg-teas-attachment-circuit] specifies YANG data models
   for bearers and 'Attachment circuits'-as-a-service ACaaS.  Layer 3
   UDP tunnel as bearer is not defined in the ACaaS specification and is
   an extension defined in this document.  An example of Layer 3 UDP
   tunnel as a bearer is in 5G networks where a GTP-U (UDP) bearer is
   used to transport datagrams of a mobile end-user between 3GPP user
   plane functions.  Section 2 describes the "ietf-ac-udpt" YANG module
   for Layer 3 UDP tunnel service.  Section 3 describes the UDP tunnel



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   YANG data model.  An example of UDP Tunnel with source port number to
   identify bearers at the transport network Provider Edge (PE) is
   provided in Appendix B.

2.  Attachment Circuit for UDP Tunnel

   [I-D.ietf-opsawg-teas-attachment-circuit] defines a YANG service
   model for AC based on layer 2 bearers.  This document extends the
   YANG service model for AC in
   [I-D.ietf-opsawg-teas-attachment-circuit] to support UDP tunnels.

   The 'l3-service' and 'l3-tunnel-service' in the AC structure in
   [I-D.ietf-opsawg-teas-attachment-circuit] is used to configure the
   relevant layer 3 tunnel properties of a UDP tunnel AC.  IPv4 and IPv6
   properties of the UDP tunnel AC are provided in the "ip-connection"
   container (Section 5.2.5.2 of
   [I-D.ietf-opsawg-teas-attachment-circuit]).  The extension below adds
   source port number and range for the UDP tunnel.

   The meanings of the symbols in the YANG tree diagram are defined in
   "YANG Tree Diagrams" [RFC8340].


   module: ietf-ac-udpt

     augment /ac-svc:attachment-circuits/ac-svc:ac/ac-svc:ip-connection
             /ac-svc:l3-service/ac-svc:l3-tunnel-service
             /ac-svc:l3-tunnel-service:

       +--rw (udp-port)?
          +--:(port-range-or-operator)
             +--rw source-port-range-or-operator
                +--rw (port-range-or-operator)?
                   +--:(range)
                   |  +--rw lower-port    inet:port-number
                   |  +--rw upper-port    inet:port-number
                   +--:(operator)
                      +--rw operator?     operator
                      +--rw port          inet:port-number


                      Figure 1: UDP Tunnel Yang Module

   'l3-tunnel-service' in Section 5.2.5.2 of
   [I-D.ietf-opsawg-teas-attachment-circuit] is extended in this
   document to specify UDP source port number or a range port numbers.





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   Also, this document defines a new identity (called 'udp') based on
   the base identity 'l3-tunnel-type' defined in Section 4.2 of
   [I-D.ietf-opsawg-teas-common-ac].

3.  ietf-ac-udp-tunnel YANG Module

   The "ietf-ac-udp-tunnel" module uses types and groupings defined in
   [I-D.ietf-opsawg-teas-common-ac],
   [I-D.ietf-opsawg-teas-attachment-circuit], and [RFC8519].

   <CODE BEGINS> file "ietf-ac-udp-tunnel@2025-09-18.yang"
   module ietf-ac-udp-tunnel {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:ietf-ac-udp-tunnel";
     prefix ac-udpt;

     import ietf-ac-common {
       prefix ac-common;
       reference
         "RFC 9833: A Common YANG Data Model for Attachment Circuits";
     }
     import ietf-ac-svc {
       prefix ac-svc;
       reference
         "RFC 9834: YANG Data Models for Bearers and 'Attachment
                    Circuits'-as-a-Service (ACaaS)";
     }
     import ietf-packet-fields {
       prefix packet-fields;
         reference
           "RFC 8519: YANG Data Model for Network Access
                      Control Lists (ACLs), Section 4.2";
     }

     organization
       "IETF DMM (Distributed Mobility Management)";
     contact
       "WG Web:   <https://datatracker.ietf.org/wg/dmm/>
        WG List:  <mailto:dmm@ietf.org>

        Author:   John Kaippallimalil
                  <mailto:john.kaippallimalil@futurewei.com>";
     description
       "This YANG module defines a YANG model for augmenting
        the ACaaS service model with UDP Encapsulation as
        Layer 3 tunnel service.

        Copyright (c) 2025 IETF Trust and the persons identified as



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        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 Revised BSD License
        set forth in Section 4.c of the IETF Trust's Legal Provisions
        Relating to IETF Documents
        (https://trustee.ietf.org/license-info).

        All revisions of IETF and IANA published modules can be found
        at the YANG Parameters registry group
        (https://www.iana.org/assignments/yang-parameters).

        This version of this YANG module is part of RFC XXXX; see the
        RFC itself for full legal notices.";

     revision 2025-09-18 {
       description
         "Initial revision.";
       reference
         "RFC XXXX: A YANG Data Model for Attachment Circuit
                    as a Service with UDP Tunnel Support";
     }

     identity udp {
       base ac-common:l3-tunnel-type;
       description
         "UDP Encapsulation.";
       reference
         "RFC 8085: UDP Usage Guidelines, Section 3.1.11";
     }

     augment "/ac-svc:attachment-circuits/ac-svc:ac"
           + "/ac-svc:ip-connection/ac-svc:l3-service"
           + "/ac-svc:l3-tunnel-service/ac-svc:l3-tunnel-service" {
       when "derived-from-or-self(./type, 'ac-udpt:udp')" {
         description
           "Only applicable if l3 service type is UDP encapsulation.";
       }
       description
         "Augments Layer 3 AC service with required data nodes for
          UDP encapsulation support.";
        choice udp-port {
          description
            "Choice of specifying the source port number or referring
             to a group of port numbers.";
          container source-port-range-or-operator {
            description



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               "Indicates a set of source ports numbers.";
            uses packet-fields:port-range-or-operator;
         }
       }
     }
   }
   <CODE ENDS>

                      Figure 2: UDP Tunnel YANG Module

   Note to RFC Editor:

      Replace "RFC XXXX" with the RFC number to be assigned to this
      document.

4.  Acknowledgements

   Thanks to Mohamed Boucadair for the review and comments.

5.  Security Considerations

   This section is modeled after the template described in Section 3.7
   of [I-D.ietf-netmod-rfc8407bis].

   The "ietf-ac-udp-tunnel" YANG module defines a data model that is
   designed to be accessed via YANG-based management protocols, such as
   NETCONF [RFC6241] and RESTCONF [RFC8040].  These YANG-based
   management protocols (1) have to use a secure transport layer (e.g.,
   SSH [RFC4252], TLS [RFC8446], and QUIC [RFC9000]) and (2) have to use
   mutual authentication.

   Servers MUST verify that requesting clients are entitled to access
   and manipulate a given bearer or AC.  For example, a given customer
   must not have access to bearers (attachment circuits) of other
   customers.  The Network Configuration Access Control Model (NACM)
   [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.

   The data nodes in the YANG model in this document inherits from
   [I-D.ietf-opsawg-teas-attachment-circuit], and the security
   constraints to the data structures there apply.  Data nodes defined
   in the ietf-ac-udp-tunnel YANG module 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) and delete
   operations to these data nodes without proper protection or
   authentication can have a negative effect on network operations.  The



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   'udp-port' information may be used to track a customer of the slice
   service and may be considered a violation of the customer-provider
   trust relationship.

6.  IANA Considerations

   IANA is requested to register the following URI in the "ns"
   subregistry within the "IETF XML Registry" [RFC3688]:

      URI: urn:ietf:params:xml:ns:yang:ietf-ac-udp-tunnel

      Registrant Contact: The IESG.

      XML: N/A; the requested URI is an XML namespace.

   IANA is requested to register the following YANG module in the "YANG
   Module Names" subregistry [RFC6020] within the "YANG parameters"
   registry.

      Name: ietf-ac-udp-tunnel

      Maintained by IANA?  N

      Namespace: urn:ietf:params:xml:ns:yang:ietf-ac-udp-tunnel

      Prefix: ac-udp-tunnel

      Reference: RFC XXXX

7.  References

7.1.  Normative References

   [I-D.ietf-opsawg-teas-attachment-circuit]
              Boucadair, M., Roberts, R., de Dios, O. G., Barguil, S.,
              and B. Wu, "YANG Data Models for Bearers and 'Attachment
              Circuits'-as-a-Service (ACaaS)", Work in Progress,
              Internet-Draft, draft-ietf-opsawg-teas-attachment-circuit-
              20, 23 January 2025,
              <https://datatracker.ietf.org/doc/html/draft-ietf-opsawg-
              teas-attachment-circuit-20>.










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   [I-D.ietf-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-ietf-
              opsawg-teas-common-ac-15, 23 January 2025,
              <https://datatracker.ietf.org/doc/html/draft-ietf-opsawg-
              teas-common-ac-15>.

   [RFC8519]  Jethanandani, M., Agarwal, S., Huang, L., and D. Blair,
              "YANG Data Model for Network Access Control Lists (ACLs)",
              RFC 8519, DOI 10.17487/RFC8519, March 2019,
              <https://www.rfc-editor.org/info/rfc8519>.

7.2.  Informative References

   [I-D.ietf-netmod-rfc8407bis]
              Bierman, A., Boucadair, M., and Q. Wu, "Guidelines for
              Authors and Reviewers of Documents Containing YANG Data
              Models", Work in Progress, Internet-Draft, draft-ietf-
              netmod-rfc8407bis-28, 5 June 2025,
              <https://datatracker.ietf.org/doc/html/draft-ietf-netmod-
              rfc8407bis-28>.

   [RFC3688]  Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
              DOI 10.17487/RFC3688, January 2004,
              <https://www.rfc-editor.org/info/rfc3688>.

   [RFC4252]  Ylonen, T. and C. Lonvick, Ed., "The Secure Shell (SSH)
              Authentication Protocol", RFC 4252, DOI 10.17487/RFC4252,
              January 2006, <https://www.rfc-editor.org/info/rfc4252>.

   [RFC6020]  Bjorklund, M., Ed., "YANG - A Data Modeling Language for
              the Network Configuration Protocol (NETCONF)", RFC 6020,
              DOI 10.17487/RFC6020, October 2010,
              <https://www.rfc-editor.org/info/rfc6020>.

   [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>.

   [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>.

   [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>.



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   [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>.

   [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>.

   [RFC8972]  Mirsky, G., Min, X., Nydell, H., Foote, R., Masputra, A.,
              and E. Ruffini, "Simple Two-Way Active Measurement
              Protocol Optional Extensions", RFC 8972,
              DOI 10.17487/RFC8972, January 2021,
              <https://www.rfc-editor.org/info/rfc8972>.

   [RFC9000]  Iyengar, J., Ed. and M. Thomson, Ed., "QUIC: A UDP-Based
              Multiplexed and Secure Transport", RFC 9000,
              DOI 10.17487/RFC9000, May 2021,
              <https://www.rfc-editor.org/info/rfc9000>.

   [RFC9543]  Farrel, A., Ed., Drake, J., Ed., Rokui, R., Homma, S.,
              Makhijani, K., Contreras, L., and J. Tantsura, "A
              Framework for Network Slices in Networks Built from IETF
              Technologies", RFC 9543, DOI 10.17487/RFC9543, March 2024,
              <https://www.rfc-editor.org/info/rfc9543>.

Appendix A.  Abbreviations

   AC –     Attachment Circuit

   CE –     Customer Edge

   GTP-U –  General Packet Radio Service (GPRS) Tunneling Protocol -
            User plane (3GPP)

   GW –     Gateway

   NSC –    Network Slice Controller

   PE –     Service Function

   SF –     Provider Edge

   SMO –    Service Management and Orchestration

   TN –     Transport Network

   UDP –    User Datagram Protocol



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Appendix B.  Example

   This example is adapted from Appendix A.7 of
   [I-D.ietf-opsawg-teas-attachment-circuit] where details of the
   topology and service are described.  Figure 3 describes the end-to-
   end network topology as well as orchestration scope:

   *  The topology is made up of two sites ("site1" and "site2"),
      interconnected via a Transport Network (e.g., IP/MPLS network).
      An SF is deployed within each site in a dedicated IP subnet.

   *  A 5G Service Management and Orchestration (SMO) is responsible for
      the deployment of SFs and the indirect management of a local
      Gateway (i.e., CE).

   *  An IETF Network Slice Controller (NSC) [RFC9543] is responsible
      for the deployment of IETF Network Slices across the Transport
      Network.



            5G SMO                 IETF NSC                 5G SMO
               |               (TN Orchestrator)               |
               |                        |                      |
         <-----+----->        <---------+-------->        <----+---->
             Site1             Transport Network              Site2
                                .--------------.
                                |              |
                              .---.          .---.
         .---.   .---.        |   |          |   |        .---.  .---.
         |SF1+----------------+PE1|          |PE2+---------------|SF2|
         '---'   |GW1|  ^     |   |          |   |   ^    |GW2|  '---'
                 '---'  |     '-+-'          '-+-'   |    '---'
                        |       |              |     |
                        |       '--------------'     |
                        |                            |
                        |                            |
                 UDP Tunnel Bearer:           UDP Tunnel Bearer:
                    bearerX@site1               bearerX@site2



      Figure 3: An example of a Network Topology to Deploy Slices with
                             UDP Tunnel Bearer

   Figure 4 describes the logical connectivity enforced with IETF
   Network slice and ACaaS models with UDP tunnel bearer identified by
   the UDP source port number.



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                                   AS 65536  <----BGP--> AS 65550
       .---.                     .--------.                     .---.
       |SF1|       192.0.2.0/30  |        |    192.0.2.4/30     |SF2|
       '-+-'   .---.           .-+-.    .-+-.           .---.   '-+-'
         |     |   |.1       .2|   |    |   |.6       .5|   |     |
       --+-----+GW1+-----------+PE1|    |PE2+-----------+GW2+-----+--
               |   |udp-src-prt|   |    |   |udp-src-prt|   |
               '---'    5678   '-+-'    '-+-'   7890    '---'
      198.51.100.0/24            |        |           203.0.113.0/24
                                 '--------'
                              sdp1        sdp2
        <--------------------> <-----------> <------------------>
                   Attachment  Network Slice  Attachment

        * "ac1" properties:
       - bearer-reference: bearerX@site1
       - udp-src-prt: 5678
       - CE address (SF1): 198.51.100.0/24
       - PE address: 192.0.2.2/30
       - Routing: static 198.51.100.0/24 via
                  192.0.2.1 tag primary_UP_slice

       * "ac2" properties:
       - bearer-reference: bearerY@site2
       - udp-src-prt: 7890
       - CE address (SF2): 203.0.113.0/24
       - PE address: 192.0.2.6/30
       - Routing: BGP local-as: 65536 (Provider ASN)
                      peer-as: 65550 (customer ASN)
                      remote-address: 192.0.2.5 (Customer address)



                         Figure 4: Logical Overview

   Figure 5 is an adaptation of A.7, Figure 41 in
   [I-D.ietf-opsawg-teas-attachment-circuit] with a UDP Tunnel bearer
   identified by the source port number.


   =============== NOTE: '\' line wrapping per RFC 8792 ================

   {
     "ietf-ac-svc:attachment-circuits": {
       "ac": [
         {
           "name": "ac1",
           "description": "Connection to site1 on vlan 100",



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           "requested-start": "2023-12-12T05:00:00.00Z",
           "l2-connection": {
             "bearer-reference": "bearerX@site1"
           },
           "ip-connection": {
             "ipv4": {
               "address-allocation-type": "ietf-ac-common:static-\
                                                                address"
             },
             "l3-service" {
               "l3-tunnel-service": "ietf-ac-udpt:udp"
             }
           },
           "routing-protocols": {
             "routing-protocol": [
               {
                 "id": "1",
                 "type": "ietf-vpn-common:static-routing",
                 "static": {
                   "cascaded-lan-prefixes": {
                     "ipv4-lan-prefix": [
                       {
                         "lan": "198.51.100.0/24",
                         "next-hop": "192.0.2.1",
                         "lan-tag": "primary_UP_slice"
                       }
                     ]
                   }
                 }
               }
             ]
           }
         },
         {
           "name": "ac2",
           "description": "Connection to site2 on vlan 200",
           "requested-start": "2023-12-12T05:00:00.00Z",
           "l2-connection": {

             "bearer-reference": "bearerY@site2"
           },
           "ip-connection": {
             "ipv4": {
               "address-allocation-type": "ietf-ac-common:static-\
                                                                address"
             },
             "l3-service" {
               "l3-tunnel-service": "ietf-ac-udpt:udp"



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             }
           },
           "routing-protocols": {
             "routing-protocol": [
               {
                 "id": "1",
                 "type": "ietf-vpn-common:bgp-routing",
                 "bgp": {
                   "neighbor": [
                     {
                       "id": "1",
                       "peer-as": 65550
                     }
                   ]
                 }
               }
             ]
           }
         }
       ]
     }
   }


   Figure 5: Message Body of a Request to Create AC with UDP Tunnel

   Figure 6 is an adaptation of A.7, Figure 42 in
   [I-D.ietf-opsawg-teas-attachment-circuit] that shows the message body
   of that response to a GET request received from the controller.


       {
        "ietf-ac-svc:attachment-circuits": {
          "ac": [
            {
              "name": "ac1",
              "description": "Connection to site1 on vlan 100",
              "actual-start": "2023-12-12T05:00:00.00Z",
              "l2-connection": {
                "bearer-reference": "bearerX@site1"
              },
              "ip-connection": {
                "ipv4": {
                  "local-address": "192.0.2.2",
                  "prefix-length": 30,
                  "address": [
                    {
                      "address-id": "1",



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                      "customer-address": "192.0.2.1"
                    }
                  ]
                },
                "l3-service" {
                  "l3-tunnel-service": "ietf-udpt:udp",
                    "ietf-ac-udpt:source-port-range-or-operator" {
                        "port": 5678
                    }
                  }
                }
              },
              "routing-protocols": {
                "routing-protocol": [
                  {
                    "id": "1",
                    "type": "ietf-vpn-common:static-routing",
                    "static": {
                      "cascaded-lan-prefixes": {
                        "ipv4-lan-prefix": [
                          {
                            "lan": "198.51.100.0/24",
                            "next-hop": "192.0.2.1",
                            "lan-tag": "primary_UP_slice"
                          }
                        ]
                      }
                    }
                  }
                ]
              }
            },
            {
              "name": "ac2",
              "description": "Connection to site2 on vlan 200",
              "actual-start": "2023-12-12T05:00:00.00Z",
              "l2-connection": {
                "bearer-reference": "bearerY@site2"
              },
              "ip-connection": {
                "ipv4": {
                  "local-address": "192.0.2.6",
                  "prefix-length": 30,
                  "address": [
                    {
                      "address-id": "1",
                      "customer-address": "192.0.2.5"
                    }



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                  ]
                },
                "l3-service" {
                  "l3-tunnel-service": "ietf-udpt:udp",
                    "ietf-ac-udpt:source-port-range-or-operator" {
                        "port": 7890
                    }
                  }
                }
              },
              "routing-protocols": {
                "routing-protocol": [
                  {
                    "id": "1",
                    "type": "ietf-vpn-common:bgp-routing",
                    "bgp": {
                      "neighbor": [
                        {
                          "id": "1",
                          "peer-as": 65550,
                          "local-as": 65536
                        }
                      ]
                    }
                  }
                ]
              }
            }
          ]
        }


        Figure 6: Example of a Message Body of a Response Indicating
                            Creation of the ACs

   Figure 7 is derived from A.7, Figure 43 in
   [I-D.ietf-opsawg-teas-attachment-circuit].  Figure 7 shows the
   message body of the request to create a Slice Service bound to the
   ACs created using Figure 5.  Only references to these ACs are
   included in the Slice Service request.











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      {
        "ietf-network-slice-service:network-slice-services": {
          "slo-sle-templates": {
            "slo-sle-template": [
              {
                "id": "low-latency-template",
                "description": "Lowest latency forwarding behavior"
              }
            ]
          },
          "slice-service": [
            {
              "id": "Slice URLLC_UP",
              "description": "Dedicated TN Slice for URLLC-UP",
              "slo-sle-template": "low-latency-template",
              "status": {},
              "sdps": {
                "sdp": [
                  {
                    "id": "sdp1",
                    "ac-svc-name": [
                      "ac1"
                    ]
                  },
                  {
                    "id": "sdp2",
                    "ac-svc-name": [
                      "ac2"
                    ]
                  }
                ]
              }
            }
          ]
        }
      }


        Figure 7: Example of a Message Body of a Response Indicating
                            Creation of the ACs

Authors' Addresses

   John Kaippallimalil
   Futurewei
   United States of America
   Email: john.kaippallimalil@futurewei.com




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   Luis M. Contreras
   Telefonica
   Telefonica Sur-3 building, 3rd floor
   28050 Madrid
   Spain
   Email: luismiguel.contrerasmurillo@telefonica.com


   Uma Chunduri
   Intel Corporation
   2191 Laurelwood Rd
   Santa Clara, CA 95054
   United States of America
   Email: umac.ietf@gmail.com





































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