Internet DRAFT - draft-dhody-teas-te-traffic-yang

draft-dhody-teas-te-traffic-yang







TEAS Working Group                                              D. Dhody
Internet-Draft                                                    Huawei
Intended status: Standards Track                            4 March 2024
Expires: 5 September 2024


        Traffic Mapping YANG model for Traffic Engineering (TE)
                  draft-dhody-teas-te-traffic-yang-04

Abstract

   This document provides a YANG data model to map traffic to Traffic
   Engineering (TE) paths.  This model providers operator a seamless
   control and management of which traffic to send on the underlying TE
   resources.

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 5 September 2024.

Copyright Notice

   Copyright (c) 2024 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents (https://trustee.ietf.org/
   license-info) in effect on the date of publication of this document.
   Please review these documents carefully, as they describe your rights
   and restrictions with respect to this document.  Code Components
   extracted from this document must include 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.





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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Conventions . . . . . . . . . . . . . . . . . . . . . . . . .   3
     2.1.  Tree Diagrams . . . . . . . . . . . . . . . . . . . . . .   3
     2.2.  Prefixes in Data Node Names . . . . . . . . . . . . . . .   4
     2.3.  References in the Model . . . . . . . . . . . . . . . . .   5
   3.  Discussion Items  . . . . . . . . . . . . . . . . . . . . . .   5
   4.  Tree Structure  . . . . . . . . . . . . . . . . . . . . . . .   5
   5.  YANG Model  . . . . . . . . . . . . . . . . . . . . . . . . .   6
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .  13
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  13
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  13
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .  13
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  15
   Appendix A.  Acknowledgments  . . . . . . . . . . . . . . . . . .  15
   Appendix B.  Examples . . . . . . . . . . . . . . . . . . . . . .  15
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .  15

1.  Introduction

   Data models are a representation of objects that can be configured or
   monitored within a system.  Within the IETF, YANG [RFC7950] is the
   language of choice for documenting data models, and YANG models have
   been produced to allow configuration or modeling of a variety of
   network devices, protocol instances, and network services.

   There are various YANG models to establish paths in the network, such
   as:

   *  TE Tunnels [I-D.ietf-teas-yang-te]

   *  Segment Routing (SR) Policy [I-D.ietf-spring-sr-policy-yang]

   *  Service Function Chaining (SFC)

   *  Virtual Network (VN)

   *  IETF Network Slice

   These models do not include an exact mechanism to describe the
   traffic that needs to be mapped to the paths.  Thus an operator lacks
   a way to simply use the YANG model to tell requirements such as the
   traffic from source X on port Y should go on a TE path with delay
   less than Z.  The YANG model defined in this document fills this gap.

   To achieve this goal, the YANG model defined in this document
   utilizes the concept borrowed from:



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   *  BGP FlowSpec: Where the description of traffic flows is done by
      the combination of multiple Flow Specification Components and
      their dissemination as traffic flow specifications (Flow
      Specifications) is described for BGP in [RFC8955].  In BGP, a Flow
      Specification is comprised of traffic filtering rules and is
      associated with actions to perform on the packets that match the
      Flow Specification.  The BGP routers that receive a Flow
      Specification can classify received packets according to the
      traffic filtering rules and can direct packets based on the
      associated actions.

   *  Path Computation Element (PCE) FlowSpec: Extends the idea to PCE
      Communication Protocol (PCEP) [RFC9168].

   *  Access Control List (ACL): A basic elements used to configure
      device-forwarding behavior in form of a user-ordered set of rules
      that is used to filter traffic on a networking device.  Each rule
      is represented by an Access Control Entry (ACE).  Each ACE has a
      group of match criteria and a group of actions [RFC8519].

   *  Flow: Elements in the packet in IP/UDP/TCP header to match
      particular flows.

   The YANG model includes two key concepts:

   *  Traffic Description: The various fields that needs to be matched
      to identify a traffic flow.

   *  Action: The associated action that needs to be taken.  For the
      purpose of this YANG model the action is to simply point to the TE
      resource in form of the TE tunnel, SR Policy etc.

   Note: The RFC Editor will replace XXXX with the number assigned to
   the RFC once this draft becomes an RFC.

2.  Conventions

   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.

2.1.  Tree Diagrams

   A simplified graphical representation of the data model is used in
   this document.  The meaning of the symbols in these diagrams is
   defined in [RFC8340].



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2.2.  Prefixes in Data Node Names

   In this document, names of data nodes and other data model objects
   are often used without a prefix, as long as it is clear from the
   context in which YANG module each name is defined.  Otherwise, names
   are prefixed using the standard prefix associated with the
   corresponding YANG module, as shown in Table 1.

   +=========+==========+=============================================+
   | Prefix  |   YANG   |                                   Reference |
   |         |  module  |                                             |
   +=========+==========+=============================================+
   | inet    |  ietf-   |                                   [RFC6991] |
   |         |  inet-   |                                             |
   |         |  types   |                                             |
   +---------+----------+---------------------------------------------+
   | yang    |  ietf-   |                                   [RFC6991] |
   |         |  yang-   |                                             |
   |         |  types   |                                             |
   +---------+----------+---------------------------------------------+
   | te      | ietf-te  |                     [I-D.ietf-teas-yang-te] |
   +---------+----------+---------------------------------------------+
   | rt      |  ietf-   |                                   [RFC8349] |
   |         | routing  |                                             |
   +---------+----------+---------------------------------------------+
   | sr-     | ietf-sr- |            [I-D.ietf-spring-sr-policy-yang] |
   | policy  |  policy  |                                             |
   +---------+----------+---------------------------------------------+
   | ietf-   |  ietf-   | [I-D.ietf-teas-ietf-network-slice-nbi-yang] |
   | nss     | network- |                                             |
   |         |  slice-  |                                             |
   |         | service  |                                             |
   +---------+----------+---------------------------------------------+
   | acl     |  ietf-   |                                   [RFC8519] |
   |         | access-  |                                             |
   |         | control- |                                             |
   |         |   list   |                                             |
   +---------+----------+---------------------------------------------+
   | packet- |  ietf-   |                                   [RFC8519] |
   | fields  | packet-  |                                             |
   |         |  fields  |                                             |
   +---------+----------+---------------------------------------------+
   | vpn-    |  ietf-   |                                   [RFC9181] |
   | common  |   vpn-   |                                             |
   |         |  common  |                                             |
   +---------+----------+---------------------------------------------+

                                 Table 1



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2.3.  References in the Model

   Following documents are referenced in the model defined in this
   document -

    +=============================+==================================+
    | Document                    |            Reference             |
    +=============================+==================================+
    | YANG Data Model for Network |            [RFC8519]             |
    | Access Control Lists (ACLs) |                                  |
    +-----------------------------+----------------------------------+
    | A YANG Data Model for       |     [I-D.ietf-teas-yang-te]      |
    | Traffic Engineering Tunnels |                                  |
    | and Interfaces              |                                  |
    +-----------------------------+----------------------------------+
    | YANG Data Model for Segment | [I-D.ietf-spring-sr-policy-yang] |
    | Routing Policy              |                                  |
    +-----------------------------+----------------------------------+

                                 Table 2

3.  Discussion Items

   For describing the traffic, currently the YANG models uses:

   *  The match criteria grouping from the
      [I-D.ietf-teas-ietf-network-slice-nbi-yang].  If this document
      gets WG backing, then it might be a good idea to move the grouping
      to this document instead.

   *  The ACL Name.  Should that be ACE instead?

   *  The match action granularity in case of IETF network slice and VN
      needs to be discussed.

   *  The match action for SFC is not handled yet.

4.  Tree Structure













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   module: ietf-traffic-map
     +--rw traffic-map
        +--rw maps* [id]
           +--rw id         string
           +--rw traffic
           |  +--rw id?                      string
           |  +--rw (type)?
           |     +--:(match-criteria)
           |     |  +--rw match-criterion* [index]
           |     |     +--rw index         uint32
           |     |     +--rw match-type    identityref
           |     |     +--rw value*        string
           |     +--:(acl)
           |     |  +--rw acl?               -> /acl:acls/acl/name
           |     +--:(flowspec)
           |     +--:(interface)
           |     |  +--rw node?              string
           |     |  +--rw if-name?           string
           |     +--:(flow)
           |     |  +--rw (l3)?
           |     |  |  +--:(ipv4)
           |     |  |  |  +--rw ipv4
           |     |  |  |        ...
           |     |  |  +--:(ipv6)
           |     |  |     +--rw ipv6
           |     |  |           ...
           |     |  +--rw (l4)?
           |     |     +--:(tcp)
           |     |     |  +--rw tcp
           |     |     |        ...
           |     |     +--:(udp)
           |     |        +--rw udp
           |     |              ...
           |     +--:(other)
           +--rw action
           |  +--rw te-tunnel*   te:tunnel-ref
           |  +--rw sr-policy* [headend policy-color-ref policy-endpoint-ref]
           |  |  +--rw headend                inet:ip-address-no-zone
           |  |  +--rw policy-color-ref       leafref
           |  |  +--rw policy-endpoint-ref    leafref
           |  +--rw other
           +--ro stats
              +--ro matched-packets?   yang:counter64
              +--ro matched-octets?    yang:counter64

5.  YANG Model





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   <CODE BEGINS> file "ietf-traffic-map@2024-03-04.yang"
   module ietf-traffic-map {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:ietf-traffic-map";
     prefix tm;

     import ietf-inet-types {
       prefix inet;
       reference
         "RFC 6991: Common YANG Data Types";
     }
     import ietf-yang-types {
       prefix yang;
       reference
         "RFC 6991: Common YANG Data Types";
     }
     import ietf-te {
       prefix te;
       reference
         "I-D.ietf-teas-yang-te: A YANG Data Model for Traffic
          Engineering Tunnels and Interfaces";
     }
     import ietf-routing {
       prefix rt;
       reference
         "RFC8349: A YANG Data Model for Routing Management";
     }
     import ietf-sr-policy {
       prefix sr-policy;
       reference
         "I-D.ietf-spring-sr-policy-yang: YANG Data Model for Segment
          Routing Policy";
     }
     import ietf-network-slice-service {
       prefix ietf-nss;
       reference
         "I-D.ietf-teas-ietf-network-slice-nbi-yang: IETF
          Network Slice Service YANG Model";
     }
     import ietf-packet-fields {
       prefix packet-fields;
       reference
         "RFC 8519: YANG Data Model for Network Access
          Control Lists (ACLs)";
     }
     import ietf-access-control-list {
       prefix acl;
       reference



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         "RFC 8519: YANG Data Model for Network Access Control
          Lists (ACLs)";
     }
     import ietf-vpn-common {
       prefix vpn-common;
       reference
         "RFC 9181: A Common YANG Data Model for Layer 2 and
          Layer 3 VPNs";
     }

     organization
       "IETF Traffic Engineering Architecture and Signaling (TEAS)
        Working Group";
     contact
       "WG Web:  <https://datatracker.ietf.org/wg/teas/about/>
        WG List:  <mailto:teas@ietf.org>
        Editor: Dhruv Dhody <dhruv.ietf@gmail.com>";
     description
       "This module contains a YANG module to map traffic to
        Traffic Engineering (TE) paths.

        Copyright (c) 2022 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 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).

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

     revision 2024-03-04 {
       description
         "initial version.";
       reference
         "RFC XXXX: Traffic Mapping YANG model for Traffic
          Engineering (TE)";
     }

     grouping traffic-description {
       description
         "The traffic description";
       leaf id {
         type string;
         description



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           "The identifier for Traffic Description";
       }
       choice type {
         description
           "The various ways the traffic can be described";
         case match-criteria {
           description
             "Use the match criteria";
           list match-criterion {
             key "index";
             description
               "List of traffic match criteria.";
             leaf index {
               type uint32;
               description
                 "The entry index.";
             }
             leaf match-type {
               type identityref {
                 base ietf-nss:service-match-type;
               }
               mandatory true;
               description
                 "Identifies an entry in the list of the
                  match criteria.";
             }
             leaf-list value {
               type string;
               description
                 "Describes the slice service match criteria, e.g.
                  IP address, VLAN, etc.";
             }
           }
         }
         case acl {
           description
             "Reference to ACL";
           leaf acl {
             type leafref {
               path "/acl:acls/acl:acl/acl:name";
             }
             description
               "The ACL Name. The action part of the ACL is not
                used.";
             reference
               "RFC8519: YANG Data Model for Network Access Control
                Lists (ACLs)";
           }



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         }
         case flowspec {
           description
             "Based on FlowSpec component type - TODO";
         }
         case interface {
           description
             "All traffic received on an interface";
           leaf node {
             type string;
             description
               "The node identifier";
           }
           leaf if-name {
             type string;
             description
               "The interface name on the node";
           }
         }
         case flow {
           description
             "Match particular flows";
           choice l3 {
             description
               "Either IPv4 or IPv6.";
             container ipv4 {
               description
                 "Rule set that matches the IPv4 header.";
               uses packet-fields:acl-ip-header-fields;
               uses packet-fields:acl-ipv4-header-fields;
             }
             container ipv6 {
               description
                 "Rule set that matches the IPv6 header.";
               uses packet-fields:acl-ip-header-fields;
               uses packet-fields:acl-ipv6-header-fields;
             }
           }
           choice l4 {
             description
               "Includes Layer-4-specific information.
                This version focuses on TCP and UDP.";
             container tcp {
               description
                 "Rule set that matches the TCP header.";
               uses packet-fields:acl-tcp-header-fields;
               uses vpn-common:ports;
             }



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             container udp {
               description
                 "Rule set that matches the UDP header.";
               uses packet-fields:acl-udp-header-fields;
               uses vpn-common:ports;
             }
           }
         }
         case other {
           description
             "TODO";
         }
       }
     }

     grouping te-ref {
       description
         "Reference to TE paths";
       leaf-list te-tunnel {
         type te:tunnel-ref;
         description
           "Reference to TE Tunnels";
         reference
           "I-D.ietf-teas-yang-te: A YANG Data Model for Traffic
            Engineering Tunnels and Interfaces";
       }
       list sr-policy {
         key "headend policy-color-ref policy-endpoint-ref";
         description
           "SR Policy";
         reference
           "I-D.ietf-spring-sr-policy-yang: YANG Data Model for
            Segment Routing Policy";
         /*Headend needs to be added*/
         leaf headend {
           type inet:ip-address-no-zone;
           description
             "SR Policy headend";
         }
         leaf policy-color-ref {
           type leafref {
             path "/rt:routing/sr-policy:segment-routing"
                + "/sr-policy:traffic-engineering/sr-policy:policies"
                + "/sr-policy:policy/sr-policy:color";
           }
           description
             "Reference to sr-policy color";
         }



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         leaf policy-endpoint-ref {
           type leafref {
             path "/rt:routing/sr-policy:segment-routing"
                + "/sr-policy:traffic-engineering/sr-policy:policies"
                + "/sr-policy:policy/sr-policy:endpoint";
           }
           description
             "Reference to sr-policy endpoint";
         }
       }
       container other {
         description
           "To dp - VN, IETF Network Slice, SFC etc";
       }
     }

     /* Configuration data nodes */

     container traffic-map {
       description
         "AP configurations";
       list maps {
         key "id";
         description
           "traffic map identifier";
         leaf id {
           type string;
           description
             "The identifier for Traffic Maps";
         }
         container traffic {
           description
             "The traffic description";
           uses traffic-description;
         }
         container action {
           description
             "The action is limited to identifying the TE resource";
           uses te-ref;
         }
         container stats {
           config false;
           description
             "Statistics";
           leaf matched-packets {
             type yang:counter64;
             description
               "The number of packets that matched the traffic



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                description";
           }
           leaf matched-octets {
             type yang:counter64;
             description
               "The number of octets (byte) that matched the traffic
                description";
           }
         }
       }
     }
   }

   <CODE ENDS>

6.  Security Considerations

   TBD

7.  IANA Considerations

   IANA is requested to make the following allocation for the URIs in
   the "ns" subregistry within the "IETF XML Registry" [RFC3688]:

    --------------------------------------------------------------------
    URI: urn:ietf:params:xml:ns:yang:ietf-traffic-map
    Registrant Contact: The IESG.
    XML: N/A, the requested URI is an XML namespace.
    --------------------------------------------------------------------

   IANA is requested to make the following allocation for the YANG
   module in the "YANG Module Names" registry [RFC6020]:

    --------------------------------------------------------------------
    name:         ietf-traffic-map
    namespace:    urn:ietf:params:xml:ns:yang:ietf-traffic-map
    prefix:       tm
    reference:    RFC XXXX
    --------------------------------------------------------------------

8.  References

8.1.  Normative References

   [I-D.ietf-spring-sr-policy-yang]
              Raza, S., Sawaya, R., Shunwan, Z., Voyer, D., Durrani, M.,
              Matsushima, S., and V. P. Beeram, "YANG Data Model for
              Segment Routing Policy", Work in Progress, Internet-Draft,



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              draft-ietf-spring-sr-policy-yang-02, 23 September 2022,
              <https://datatracker.ietf.org/doc/html/draft-ietf-spring-
              sr-policy-yang-02>.

   [I-D.ietf-teas-ietf-network-slice-nbi-yang]
              Wu, B., Dhody, D., Rokui, R., Saad, T., and J. Mullooly,
              "A YANG Data Model for the RFC AAAA Network Slice
              Service", Work in Progress, Internet-Draft, draft-ietf-
              teas-ietf-network-slice-nbi-yang-09, 17 February 2024,
              <https://datatracker.ietf.org/doc/html/draft-ietf-teas-
              ietf-network-slice-nbi-yang-09>.

   [I-D.ietf-teas-yang-te]
              Saad, T., Gandhi, R., Liu, X., Beeram, V. P., and I.
              Bryskin, "A YANG Data Model for Traffic Engineering
              Tunnels, Label Switched Paths and Interfaces", Work in
              Progress, Internet-Draft, draft-ietf-teas-yang-te-36, 2
              February 2024, <https://datatracker.ietf.org/doc/html/
              draft-ietf-teas-yang-te-36>.

   [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/rfc/rfc2119>.

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

   [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/rfc/rfc6020>.

   [RFC6991]  Schoenwaelder, J., Ed., "Common YANG Data Types",
              RFC 6991, DOI 10.17487/RFC6991, July 2013,
              <https://www.rfc-editor.org/rfc/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/rfc/rfc7950>.

   [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/rfc/rfc8174>.






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   [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/rfc/rfc8340>.

   [RFC8349]  Lhotka, L., Lindem, A., and Y. Qu, "A YANG Data Model for
              Routing Management (NMDA Version)", RFC 8349,
              DOI 10.17487/RFC8349, March 2018,
              <https://www.rfc-editor.org/rfc/rfc8349>.

   [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/rfc/rfc8519>.

   [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, February
              2022, <https://www.rfc-editor.org/rfc/rfc9181>.

8.2.  Informative References

   [RFC8955]  Loibl, C., Hares, S., Raszuk, R., McPherson, D., and M.
              Bacher, "Dissemination of Flow Specification Rules",
              RFC 8955, DOI 10.17487/RFC8955, December 2020,
              <https://www.rfc-editor.org/rfc/rfc8955>.

   [RFC9168]  Dhody, D., Farrel, A., and Z. Li, "Path Computation
              Element Communication Protocol (PCEP) Extension for Flow
              Specification", RFC 9168, DOI 10.17487/RFC9168, January
              2022, <https://www.rfc-editor.org/rfc/rfc9168>.

Appendix A.  Acknowledgments

   Thanks to Adrian Farrel for the motivation behind this document.

Appendix B.  Examples

   TO be added in future revisions.

Author's Address

   Dhruv Dhody
   Huawei
   India
   Email: dhruv.ietf@gmail.com






Dhody                   Expires 5 September 2024               [Page 15]