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 <!-- ***** FRONT MATTER ***** -->

 <front>
    <!-- The abbreviated title is used in the page header - it is only necessary if the 
        full title is longer than 39 characters -->

   <title abbrev="MUP Architecture">Mobile User Plane
   Architecture for Distributed Mobility Management</title>
    <seriesInfo name="Internet-Draft" value="draft-ietf-dmm-mup-architecture-01"/>
    <!-- add 'role="editor"' below for the editors if appropriate -->

   <!-- Another author who claims to be an editor -->

   <author fullname="Satoru Matsushima" initials="S." surname="Matsushima">
      <organization>SoftBank</organization>
      <address>
        <postal>
          <street/>
          <!-- Reorder these if your country does things differently -->

         <city></city>
          <region/>
          <code/>
          <country>Japan</country>
        </postal>
        <email>satoru.matsushima@g.softbank.co.jp</email>
        <!-- uri and facsimile elements may also be added -->
     </address>
    </author>
    <author fullname="Katsuhiro Horiba" initials="K." surname="Horiba">
      <organization></organization>
      <address>
        <postal>
          <street/>
          <city></city>
          <region/>
          <code/>
          <country>Japan</country>
        </postal>
        <email>katsuhiro.horiba@gmail.com</email>
      </address>
    </author>
   <author fullname="Yuya Kawakami" initials="Y." surname="Kawakami">
      <organization>SoftBank</organization>
      <address>
        <postal>
          <street/>
          <!-- Reorder these if your country does things differently -->

         <city></city>
          <region/>
          <code/>
          <country>Japan</country>
        </postal>
        <email>yuya.kawakami01@g.softbank.co.jp</email>
        <!-- uri and facsimile elements may also be added -->
     </address>
    </author>
    <author fullname="Tetsuya Murakami" initials="T." surname="Murakami">
      <organization abbrev="Arrcus, Inc">
            Arrcus, Inc.</organization>
      <address>
        <postal>
          <street/>
          <city/>
          <region/>
          <code/>
          <country>USA</country>
        </postal>
        <email>tetsuya@arrcus.com</email>
      </address>
    </author> 
    <author fullname="Keyur Patel" initials="K." surname="Patel">
      <organization abbrev="Arrcus, Inc">
            Arrcus, Inc.</organization>
      <address>
        <postal>
          <street/>
          <city/>
          <region/>
          <code/>
          <country>USA</country>
        </postal>
        <email>keyur@arrcus.com</email>
      </address>
    </author> 
    <author fullname="Jakub Horn" initials="J." surname="Horn">
      <organization abbrev="Cisco Systems, Inc.">
            Cisco Systems, Inc.</organization>
      <address>
        <postal>
          <street/>
          <city/>
          <region/>
          <code/>
          <country>Czech Republic</country>
        </postal>
        <email>jakuhorn@cisco.com</email>
      </address>
    </author> 

    <date year="2025"/>
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   <area>General</area>
    <workgroup>Internet Engineering Task Force</workgroup>
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   <keyword>mobile userplane, segment routing, SRv6</keyword>
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    <abstract>
        <t>This document defines the Mobile User Plane 
        (MUP) architecture for Distributed Mobility Management. 
        The requirements for Distributed Mobility Management described in 
        <xref target="RFC7333"/> can be satisfied by routing fashion.</t>

        <t>In MUP Architecture, session information 
        between the entities of the mobile user plane 
        is turned to routing information so that 
        mobile user plane can be integrated into dataplane.</t>
        
        <t>MUP architecture is designed to be pluggable
        user plane part of existing mobile service architectures,
        enabled by auto-discovery for the use plane. 
        Segment Routing provides network programmability
        for a scalable option with it.</t>

        <t>While MUP architecture itself is independent 
        from a specific dataplane protocol, 
        several dataplane options are available for 
        the architecture. 
        This document describes IPv6 dataplane in 
        Segment Routing case (SRv6 MUP) due to the DMM requirement, 
        and is suitable for mobile services which require 
        a large IP address space.</t>



    </abstract>
  </front>
  <middle>
    <section anchor="intro" numbered="true" toc="default">
      <name>Introduction</name>
      <t>Mobile service systems require IP connectivity for communication 
      between the entities defined by mobile service architectures for the mobile service systems.
      <xref target="RFC5213"/><xref target="TS.23501"/>. </t>
      <!--
      To provide the IP connectivity, Segment Routing (SR) 
      <xref target="RFC8402"/>can be a candidate solution.</t>
      -->

      <t>In PMIPv6 <xref target="RFC5213"/>, IP connectivity 
      is required between 
      LMA (Local Mobility Anchor) and MAG (Mobility Access Gateway), as well as LMA and 
      Internet. In 3GPP 5G <xref target="TS.23501"/>,
      IP connectivity for N3 interface between gNodeB(es) 
      and UPFs (User Plane Function) is required, as well as for N6 interface 
      between UPFs and DNs (Data Network).</t>

      <t>These IP connectivities may be covered by multiple 
      dataplane networks, such as IPv4, IPv6, MPLS, or bunch of
      dataplane protocols.
      When just one dataplane protocol network is adopted 
      for simplicity, it is expected that 
      the address space of the dataplane network should be large enough 
      to cover a vast number of nodes, such as millions of base stations. 
      For this reason, use of IPv6 dataplane looks 
      sufficiently suitable.</t>
      
      <!-- 
       while MPLS Label space in an SR network 
      is limited even though MPLS dataplane 
      may also be available for IPv6 networks.</t>
      -->

      <t>IPv6 dataplane has been able to instantiate 
      Segment Routing over IPv6 (SRv6) with 
      network programming capability described in 
      <xref target="RFC8986"/>.</t>

      <t>SRv6 network programmability enhances IPv6 dataplane 
      to be integrated with mobile user plane 
      <xref target="RFC9433"/>. 
      It will make an entire IPv6 network support the user plane 
      in a very efficient distributed routing fashion.</t>

      <t>On the other hand, the requirements for 
      Distributed Mobility Management (DMM) described in 
      <xref target="RFC7333"/> can be satisfied by session management 
      based solutions. <xref target="RFC8885"/> defines 
      protocol extension to PMIPv6 for the DMM requirements. 
      3GPP 5G defines an architecture in which 
      multiple session anchors can be added to one 
      PDU session by the session management.</t>

      <t>As a reminder, the user plane related requirements 
      in <xref target="RFC7333"/> are reproduced here:</t>

      <dl newline="true" spacing="normal" indent="8">

        <dt>REQ1: Distributed mobility management</dt>
        <dd>IP mobility, network access solutions, and forwarding 
        solutions provided by DMM MUST enable traffic to avoid 
        traversing a single mobility anchor 
        far from the optimal route. It is noted that the 
        requirement on distribution 
        applies to the data plane only.</dd>

        <dt>REQ3: IPv6 deployment</dt>
        <dd>DMM solutions SHOULD target IPv6 as the primary deployment 
        environment and SHOULD NOT be tailored specifically to support 
        IPv4, particularly in situations 
        where private IPv4 addresses and/or NATs are used.</dd>

        <dt>REQ4: Existing mobility protocols</dt>
        <dd>A DMM solution MUST first consider reusing and extending 
        IETF standard protocols before specifying new protocols.</dd>

        <dt>REQ5: Coexistence with deployed networks/hosts and 
        operability across different networks</dt>
        <dd>A DMM solution may require loose, tight, or no integration 
        into existing mobility protocols and host IP stacks. Regardless 
        of the integration level, DMM implementations MUST be able to 
        coexist with existing network deployments, end hosts, and routers 
        that may or may not implement existing mobility protocols. 
        Furthermore, a DMM solution SHOULD work across different networks, 
        possibly operated as separate administrative domains, 
        when the needed mobility management signaling, forwarding, 
        and network access are allowed by the trust relationship 
        between them.</dd>
      </dl>

      <t>This document defines the  
      Mobile User Plane (MUP) architecture
      for Distributed Mobility Management. 
      MUP is not a mobility management system itself, 
      but an architecture enables the dataplanes to integrate 
      mobile user plane into it for the IP networks.</t>
            
      <t>Although MUP architecture is independent 
      from a specific dataplane protocol, 
      this document describes IPv6 dataplane in 
      Segment Routing case (SRv6 MUP) due to the DMM requirement, 
      and as a suitable solution for scalable mobile service
      deployments. Other dataplane options is out of scope of
      this document, and may be described in the future.</t>

      <t>In this routing paradigm, a session information from 
      a mobile control plane of a mobile service system will be transformed to 
      routing information. It means that any MUP dataplane nodes
      become functional to the session instead of the mobile user plane 
      specific nodes for the role of anchor or intermediate points.
      The user plane anchor and intermediate functions 
      can be supported by MUP enabled networks (REQ1), 
      not to mention that MUP will naturally be 
      deployed over IPv6 networks (REQ3).</t>

      <t>MUP architecture is independent from the mobile 
      service system. For the requirements (REQ4, 5), 
      MUP architecture is designed to be pluggable user plane 
      part of existing mobile service architectures. 
      Those existing architectures are for example defined in 
      <xref target="RFC5213"/>, <xref target="TS.23501"/>, 
      or if any.</t>

      <t>The level of MUP integration for mobile service systems 
      running based on the existing mobile service architecture will be varied 
      and depending on the level of MUP awareness of the control 
      and user plane entities.</t>

      <t>Specifying how to modify the existing architecture to 
      integrate MUP is out of scope of this document. 
      What this document provides for the existing architecture 
      is an interface for MUP which the existing or future 
      architectures can easily integrate.</t>


      <section numbered="true" toc="default">
        <name>Requirements Language</name>
        <t>The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
       "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
       document are to be interpreted as described in <xref target="RFC2119" format="default">RFC 2119</xref>.</t>
      </section>
    </section>
    <section anchor="term" numbered="true" toc="default">
      <name>Terminology</name>
      <dl newline="false" spacing="normal" indent="8">
        <dt>MUP:</dt><dd>Mobile User Plane</dd>
        <dt>MUP Segment:</dt><dd>Representation of mobile user plane segment</dd>
        <dt>MUP PE:</dt><dd>MUP aware Provider Edge node</dd>
        <dt>MUP Controller:</dt><dd>Controller node for MUP networks</dd>
        <dt>UE:</dt><dd>User Equipment, as per <xref target="TS.23501"/></dd>
        <dt>MN:</dt><dd>Mobile Node, as per <xref target="RFC5213"/></dd>
      </dl>
    </section>
    <section anchor="principle" numbered="true" toc="default">
      <name>Architecture Principles</name>
        <t>This section describes the principles for MUP architecture that guide
        its design and operation.</t>

        <t>The first key principle is the abstraction of the mobile 
        user plane. A network segment consisting of a mobile service is 
        abstracted and represented as a MUP segment. 
        It is noted that MUP segment described in this document is 
        NOT Segment Routing<xref target="RFC8402"/> specific, 
        as "segment" is widely common terminology through 
        many networking technologies, and is defined in each technology
        context.</t>

        <t>A MUP PE may accommodate MUP segment(s), such as
        an Interwork Segment and/or a Direct Segment described in
        <xref target="mup_seg"/>. 
        <xref target="fig_overview"/> depicts the overview. 
</t>

        <figure anchor="fig_overview" title="Overview of MUP Architecture">
          <artwork align="center" type="" alt=""><![CDATA[


                        *   Mobility   *
                         * Management *
                          *  System  *
                           *........*
                                |
                       Session Information
                                |
                  ______________v______________
   _______       /           |MUP-C|           \       _______
  /       \     /            +-----+            \     /       \
 /Interwork\__  |                               |  __/ Direct  \
 \ Segment /  \ |-------+                +------| /  \ Segment /
  \_______/    \| MUP PE|       MUP      |MUP PE|/    \_______/
   _______     /|-------+     Network    +------|\     _______
  /       \   / |                               | \   /       \
 / Direct  \_/   \                              /  \_/Interwork\
 \ Segment /      \____________________________/     \ Segment /
  \_______/                                           \_______/

          ]]></artwork>
        </figure>

        <t>The second principle is auto-discovery for MUP segment.
        A MUP PE should be able to discover a MUP segment 
        in a remote MUP PE. In MUP architecture, the remote MUP PE 
        should advertise an auto-discovery route for a hosted MUP 
        segment. The MUP PE can discover the MUP segment 
        in the remote MUP PE when the MUP PE finds  the MUP segment 
        information in the received auto-discovery route 
        from the remote MUP PE.</t>

        <t><xref target="A-D_route"/> in this document defines 
        auto-discovery route for each type of MUP segment discovery.</t>

        <t>It is noted that the auto-discovery route must be 
        independent from a specific dataplane. 
        But with an attribute for the specific dataplane, 
        the auto-discovery route indicates specific dataplane 
        behavior required for the MUP segment.</t>

        <t>The third principle is that transforming 
        session information to routing information.
        Assuming session information for a UE or a MN 
        includes a pair of endpoints between the entities 
        of the mobile user plane,        
        a MUP Controller (MUP-C) advertises MUP PE(s) 
        routing information for the UE or the MN, transformed 
        from the input of corresponding session information 
        in mobile service systems. In MUP architecture,
        it is called session-transformed route.</t>

        <t><xref target="ST_route"/> in this document defines 
        each type of session-transformed route.
        The session-transformed route must also be dataplane
        independent.</t>

        <t>A MUP PE should resolve reachability for a received 
        session-transformed route (ST route for short). 
        When the MUP PE succeeds to resolve the ST route
        reachability with a MUP segment in local, or in remote 
        via an auto-discovery route, and an appropriate dataplane
        behavior indicated in it for the ST route, the MUP PE can 
        perform the dataplane action to the corresponding packet 
        received from a local MUP segment.</t>
        
        <t>The MUP PE sends the packet toward the egress MUP segment
        after the dataplane action applied to the packet. 
        The egress MUP segment may exist in local, or in a
        remote MUP PE. In latter case, the remote MUP PE applies the 
        dataplane action indicated by the received packet, 
        and sends it out to the egress MUP segment.</t>

        <t>The illustrations are described
        in <xref target="illustration"/>.</t>
        <t> To carry these new routing information, this architecture 
        requires extending the existing routing protocols. 
        Any routing protocol can be used to carry this information 
        but this document recommends using BGP. 
        Thus, this document describes extensions on BGP as an example.</t>


    </section>
    <section anchor="mup_seg" numbered="true" toc="default">
      <name>Mobile User Plane Segment</name>
      <t>This document defines two types of Mobile User Plane (MUP) 
      segment. A MUP segment represents a network segment 
      consisting of a mobile service. The MUP segment can be created by 
      a MUP PE which provides connectivity for the mobile user plane.</t>

      <t>Direct Segment is a type of MUP segment that provides 
      connectivity between MUP segments through the MUP networks. 
      Interwork Segment is another type of MUP segment. It
      provides connectivity between a user plane protocol of existing 
      or future mobile service architecture and other MUP segments
      through the MUP networks.</t>

      <t>A MUP PE may be instantiated as a physical node or a virtual node.
      The MUP PE may also be instantiated on a device which accommodates 
      a mobile user plane node of a mobile service system.</t>

    <section numbered="true" toc="default">
      <!-- <name>IPv6 Dataplane</name> -->
      <name>Dataplane Considerations</name>
      <t>As in <xref target="intro"/>, this document 
      describes IPv6 dataplane in Segment Routing case due to the 
      DMM requirement, and as a suitable solution for scalable 
      mobile service deployments.</t>

      <t>When SRv6 is adopted as the dataplane, an SRv6 SID 
      (Segment Identifier) can represent a MUP segment.
      The SID can be any behavior defined in <xref target="RFC8986"/>, 
      <xref target="RFC9433"/>, 
      or any other extensions for further use cases.
      The behavior of the MUP segment will be chosen by the role 
      of the representing MUP segment. </t>

      <t>For example, in case of a MUP PE interfaces to 5G user plane 
      on the access side defined as "N3" in <xref target="TS.23501"/>, 
      the MUP PE accommodates the N3 network as Interwork Segment in a routing
      instance and then the behavior of created segment SID by the MUP PE
      will be "End.M.GTP4.E", or "End.M.GTP6.E".
      In this case, the MUP PE may associate the SID to
      the routing instance for the N3 access network (N3RAN).</t>

      <t>Another example here is that a MUP PE interfaces to 5G DN on the 
      core side defined as "N6" in <xref target="TS.23501"/>, the MUP PE
      accommodates the N6 network in a routing instance as Direct Segment
      and then the behavior of the created segment SID by the MUP PE will be
      "End.DT4", "End.DT6", or "End.DT2".
      In this case, the MUP PE may associate the SID to
      the routing instance for the N6 data network (N6DN).</t>
    </section>
    <!--
    <section numbered="true" toc="default">
      <name>MPLS Dataplane</name>
      <t>An MPLS Label can represent a MUP segment as a SID. 
      Since it is an MPLS Label, non-SR capable MUP node can use 
      the label to send packets to the segment.</t>

      <t>For example when an MPLS dataplane PE interfaces to 5G user plane 
      on the access side defined as "N3" in <xref target="TS.23501"/>, 
      an Interwork Segment prefix is a gNB host address. The PE allocates
      an MPLS Label to the address and then set the instruction for the 
      MPLS Label to resolve the gNB address to reproduce the 5G user plane
      protocol header. Specifying that instruction is out of scope of this 
      document and it will be specified in another document.</t>

      <t>It is noted that the Interwork Segment prefix length restriction 
      for the MPLS dataplane could be mitigated or removed if 
      an <xref target="I-D.ietf-mpls-mna-fwk">
      MPLS Network Action (MNA)</xref> capable datplane is available and
      it provides similar functionalities with 
      <xref target="RFC9433"/> in the future.</t>

      <t>When an MPLS dataplane PE interfaces to 5G DN on the 
      core side defined as "N6" in <xref target="TS.23501"/>, the PE
      accommodates the N6 network in a routing instance as Direct Segment
      as same as the IPv6 dataplane case, but allocate an MPLS Label to it.
      The instruction of the MPLS Label depends on label allocation mode
      for the instance whether it is table lookup or cross-connect.
      In this case, the PE may associate the MPLS Label to lookup the table of
      the routing instance for the N6 data network (N6DN).</t>
      
    </section>
    -->
    </section>

   <section anchor="A-D_route" numbered="true" toc="default">
      <name>Distribution of Mobile User Plane Segment Information</name>
        <t>Distribution of MUP segment information can be done by 
        advertising routing information with the MUP segment for 
        mobile service. A MUP PE distributes MUP segment information when
        a MUP segment is connected to the MUP PE.</t>

        <t>A MUP Segment Discovery route is routing information
        that associates the MUP segment with network reachability, 
        and assistant metadata if applicable. 
        This document defines the basic discovery route types, 
        Direct Segment Discovery (DSD for short) route, 
        and Interwork Segment Discovery (ISD for short) route. 
        Other types of segment discovery route may be mobile service 
        architecture specific. 
        Defining the architecture specific network reachability is 
        out of scope of this document and it will be specified 
        in another document.</t>

        <t>To carry the assistant metadata for the MUP Segment Discovery
        route, this document defines MUP extended community. 
        When a metadata applicable for a set of MUP Segment, 
        a MUP extended community carries the metadata in the corresponding
        MUP Segment Discovery routes. The MUP extended community
        must be structured to indicate types of MUP segment specific metadata.
        <xref target="DSD"/> describes Direct Segment type
        MUP extended community, and is illustrated in 
        <xref target="illustration"/>.</t>

        <t>MUP Segment Discovery route MUST be used 
        only for resolving reachability for the ST routes. 
        The connectivity among the routing instances for 
        MUP Segments may be advertised as VPN routes. This is to
        avoid forwarding entries to the prefixes of the MUP Segment 
        mingled in the other type of routing instance. </t>

        <t>A MUP PE may discard the received MUP Segment Discovery route 
        if the Route Target extended communities of the route 
        does not meet the MUP PE's import policy.</t>

      <section anchor="DSD" numbered="true" toc="default">
        <name>Direct Segment Discovery (DSD) Route</name>
        <t>When a MUP PE accommodates a network, a service, 
        or an any type of resource through an interface
        or a routing instance as a Direct Segment,
        the MUP PE advertises the corresponding Direct Segment Discovery (DSD)
        route for the interface or the routing instance to the SR domain. 
        The DSD route includes an address to indicate the Direct Segment 
        in the MUP PE in the network layer reachability 
        information (NLRI) with an extended community indicating the 
        corresponding Direct Segment. Dataplane specific attribute 
        should be attached to the DSD route, as a auto-discovery route, 
        which itself must be dataplane independent defined in
         <xref target="principle"/>.</t>

        <t>For example in 3GPP 5G specific case with SRv6 dataplane, 
        an MUP PE may connect to N6 interface on a DN side, and
        a DSD route for the DN will be advertised with an address of
        the MUP PE in NLRI, an corresponding SRv6 SID in the SRv6 
        specific attribute, and a Direct Segment type MUP extended community
        to the routing instance for the DN from the MUP PE.</t>

        <t>When a MUP PE receives a DSD route from other PEs,
        the MUP PE keeps the received DSD route in the RIB.
        The MUP PE uses the received DSD route to resolve Type 2 
        Session Transformed (ST2 for short) routes reachability, described in 
        <xref target="ST2"/>.
        If the DSD route resolves reachability for the endpoints, and match the 
        Direct Segment extended community of the ST2 routes, 
        the MUP PE updates the FIB entry for the ST2 route with 
        the SID of the matched DSD route.</t>


      </section>
      <section anchor="ISD" numbered="true" toc="default">
        <name>Interwork Segment Discovery (ISD) Route</name>
        <t>When a PE accommodates a network through an interface
        or a routing instance for the user plane protocol of the mobile
        service architecture as an Interwork Segment,
        the PE advertises the corresponding Interwork Segment Discovery (ISD) 
        route with the prefixes of the Interwork Segment. 
        Dataplane specific attribute should be attached to the ISD route, 
        as a auto-discovery route, which itself must be dataplane independent 
        defined in <xref target="principle"/>. </t>

        <!--
        <t>For MPLS dataplane, the prefix length 
        of the Interwork Segment MUST be full length of IPv4 (32) or 
        IPv6 (128), due to exact match forwarding paradigm of the 
        MPLS dataplane. </t>
        -->

        <t>For example in 3GPP 5G specific case with SRv6 dataplane, 
        an MUP PE may connect to N3 network accommodating a RAN, and
        a ISD route will be advertised with IP prefix(es) of the N3 RAN 
        in NLRI, and an corresponding SRv6 SID in the SRv6 specific 
        attribute.</t>

        <t>When a MUP PE receives a ISD route, the MUP PE keeps the 
        received ISD routes in the RIB. 
        The MUP PE uses the received ISD routes to resolve the reachability 
        for remote endpoint of Type 1 Session Transformed (ST1 for short) 
        routes, described in <xref target="ST1"/>.
        If the ISD route resolves the reachability for 
        ST1 routes, the MUP PE updates 
        the FIB entry for the prefix of ST1 route 
        with the SID of the matched ISD route.</t>

        <t>The MUP PE may also use the received ISD routes to resolve 
        the reachability for the endpoint address in the ST2 route prefix.
        If the ISD route resolves the reachability for ST2 routes, 
        the MUP PE updates the FIB entry for the prefix of ST2 route 
        with the SID of the matched ISD route.</t>


      </section>
    </section>
    <section anchor="ST_route" numbered="true" toc="default">
      <name>Distribution of Session Transformed Route</name>
      <t>MUP architecture defines two types of session 
      transformed route.</t>

      <section anchor="ST1" numbered="true" toc="default">
        <name>Type 1 Session Transformed (ST1) Route</name>
        <t>First type route, called Type 1 Session Transformed (ST1) route,
        encodes IP prefix(es) for a UE or MN in a BGP
        MP-NLRI attribute with associated session information of the
        tunnel endpoint identifier on the access side. 
        The MUP-C advertises the ST1 
        route with the Route Target extended communities for the UE or MN 
        to the MUP networks.</t>

        <t>A MUP PE may receive the ST1 routes from the MUP-C
        in the MUP networks. The MUP PE may keep the received ST1
        routes advertised from the MUP-C. The receiving MUP PE will perform the
        importing of the received ST1 routes in
        the configured routing instances based on the Route Target
        extended communities. A MUP PE may discard the received ST1
        route if the MUP PE fails
        to import the route based on the Route Target extended communities.</t>
      </section>

      <section anchor="ST2" numbered="true" toc="default">
        <name>Type 2 Session Transformed (ST2) Route</name>
        <t>Second type route, called Type 2 Session Transformed (ST2) route,
        encodes the tunnel endpoint identifier of 
        the session in a BGP MP-NLRI attribute
        with the nature of tunnel endpoint base packet handling.
        Longest match algorithm for the prefix in this type of session 
        transformed route should be applicable to aggregate the routes 
        for scale. The MUP-C advertises the ST2 
        route with a Direct Segment extended community  
        to indicate corresponding Direct Segment and tunnel 
        decapsulation in addition to the Route Target extended communities</t>

        <t>A MUP PE may receive the ST2 routes
        from the MUP-C in the SR domain.
        The MUP PE may keep the received ST2 routes advertised from
        the MUP-C. The receiving MUP PE will perform the
        importing of the received ST2 routes in
        the configured routing instances based on the Route Target
        extended communities. A MUP PE may
        discard the received ST2 route if the MUP PE fails
        to import the route based on the Route Target extended communities.</t>
      </section>


      <section anchor="MUP-C" numbered="true" toc="default">
        <name>MUP Controller</name>
        <t>A MUP Controller (MUP-C) retrieves or receives session information
        for a UE or a MN from mobile service system.
        The MUP-C transforms 
        the session information to routing information and 
        will advertise the session transformed routes with the corresponding
        extended communities to the MUP networks.</t>

        <t>The session information is expected to include 
        the UE or MN IP prefix(es), tunnel endpoint identifiers for 
        both ends, and any other attributes for the mobile networks. 
        For example in a 3GPP 5G specific case, 
        the tunnel endpoint identifier will be a pair of the F-TEIDs on 
        both the N3 access side (RAN) and core side (UPF).</t>

        <t>As the MUP architecture is independent 
        from specific mobile service systems,
        the MUP-C may leverage any available interfaces or APIs 
        on the mobile service systems for the session information 
        to be received. Each mobile service system specific interface/API
        of MUP-C is out of scope of this document and 
        other documents may describe that specific interface/API.</t>
      </section>
    </section>


    <section anchor="illustration" numbered="true" toc="default">
      <name>Illustration</name>

      <t>This section illustrates possible MUP deployments with SRv6 dataplane.
      3GPP 5G is an example mobile service for the deployment cases 
      in this section. </t>

      <section anchor="deploy1" numbered="true" toc="default">
        <name>SR Network Accommodating Existing Mobile Network Services</name>

        <t><xref target="fig_deploy1"/> shows how SR networks can accommodate 
        existing mobile network service before enabling MUP.
        The PEs S1, S2, and S3 compose an SR network. 
        A routing instance is configured to each network of the mobile 
        service. N6DN in S1 and S2 are providing connectivity 
        to edge servers and the Internet respectively.</t>

        <t>VRF (Virtual Routing Forwarding) is the routing instance 
        to accommodate MUP segments in this section.
        All example cases in this section follow the typical routing policy 
        control using the BGP extended community described 
        in <xref target="RFC4360"/> and <xref target="RFC4684"/></t>

        <figure anchor="fig_deploy1" title="">
          <artwork align="center" type="" alt=""><![CDATA[
   __ N3   /-----------+-----+------------\
  /  \RAN /            |MUP-C|             \
 / V/v\_  |            +-----+             | N6   __
 \    / \ |----+                      +----| DN  /  \
  \__/   \| S1 |                      | S2 |----/W/w \
   __    /|----+                      +----|    \    /
  /  \__/ |             +----+             |     \__/
 / E/e\N6 \             | S3 |             /
 \    /DN  \------------+----+------------/
  \__/             N3UPF  /\ N6UPF
                     X/x /  \ Y/y
                       +-----+
                       | UPF |
                       +-----+
            ]]></artwork>
        </figure>

        <t>The following routing instances are configured:</t>

        <ul>
          <li>N3RAN in S1</li>
          <li>
              <ul>
                <li>export route V/v with route-target (RT) community C1</li>
                <li>import routes which have route-target (RT) community C1 and C2</li>
              </ul>
          </li>
        </ul>

        <ul>
          <li>N6DN in S1</li>
          <li>
            <ul>
              <li>export route E/e with RT C4</li>
              <li>import routes which have RT C3 and C4</li>
            </ul>
          </li>
        </ul>

        <ul>
          <li>N6DN in S2</li>
          <li>
            <ul>
              <li>export route W/w with RT C4</li>
              <li>import routes which have RT C3 and C4</li>
            </ul>
          </li>
        </ul>

        <ul>
          <li>N3UPF in S3</li>
          <li>
            <ul>
              <li>export route X/x with RT C2</li>
              <li>import routes which have RT C1</li>
            </ul>
          </li>
        </ul>

        <ul>
          <li>N6UPF in S3</li>
          <li>
            <ul>
              <li>export route Y/y with RT C3</li>
              <li>import routes which have RT C4</li>
            </ul>
          </li>
        </ul>


        <dl newline="false" spacing="normal" indent="6">
          <dt>Note: </dt>
          <dd>The above configurations are just to provide typical IP 
          connectivity for 3GPP 5G.
          When the above configurations have been done, 
          each endpoint in V/v and X/x can communicate through S1 
          and S3, but they can not communicate with nodes in 
          E/e, W/w and Y/y.</dd>
        </dl>

      </section>

      <section anchor="deploy2" numbered="true" toc="default">
        <name>MUP PE Deployment at All SR Domain Edges</name>

        <t>Here, the PEs S1, S2 and S3 are configured to enable MUP as follows:</t>

        <ul>
          <li>S1</li>
          <li>
            <ul>
              <li>advertises Interwork type discovery route: V/v with SID S1::</li>
              <li>set S1:: behavior End.M.GTP4.E or End.M.GTP6.E</li>
            </ul>
          </li>
        </ul>

        <ul>
          <li>S1</li>
          <li>
            <ul>
              <li>advertise Direct type discovery route: MUP Direct Segment community D1 and SID S1:1::</li>
              <li>set S1:1:: behavior End.DT4 or End.DT6 for the N6DN in S1</li>
            </ul>
          </li>
        </ul>

        <ul>
          <li>S2</li>
          <li>
            <ul>
              <li>advertise Direct type route: MUP Direct Segment community D1 and SID S2::</li>
              <li>set S2:: behavior End.DT4 or End.DT6 for the N6DN in S2</li>
            </ul>
          </li>
        </ul>

        <t>S1 adopts the local N6DN to prioritize the
        closer segment for the same Direct Segment. Another PE 
        may adopt D1 from S2, if the PE has no local N6DN for D1 and closer
        to S2 than S1.</t>

        <figure anchor="fig_deploy2" title="">
          <artwork align="center" type="" alt=""><![CDATA[
                         U1
                          |
U/u                       v
  \__ N3   /-----------+-----+------------\
  /  \RAN /            |MUP-C|             \
 / V/v\_  |            +-----+             | N6   __
 \    / \ |----+                      +----| DN  /  \
  \__/   \| S1 |                      | S2 |----/W/w \
   __    /|----+                      +----|    \    /
  /  \__/ |             +----+             |     \__/
 / E/e\N6 \             | S3 |             /
 \    /DN  \------------+----+------------/
  \__/             N3UPF  /\ N6UPF
                     X/x /  \ Y/y
                       +-----+
                       | UPF |
                       +-----+
            ]]></artwork>
        </figure>

        <t>Now, session information U1 is put to a MUP Controller,
        MUP-C, and MUP-C is configured to transform U1
        to the routes as follows:</t>

        <ul>
          <li>MUP-C</li>
          <li>
            <ul>
              <li>attach the MUP Direct Segment ID D1 and RT C3 to the DN in U1</li>
              <li>transforms UE's prefix U/u, the F-TEID on access side (gNB) and QFI in U1 to the ST1 route 
              for the prefix U/u with the F-TEID, the QFI, and RT C3</li>
              <li>transforms F-TEID on core side (UPF) X in U1 
              to the ST2 route for X with MUP segment-ID D1 and RT C2</li>
            </ul>
          </li>
        </ul>

        <t>Then N3RAN and N6DN import route X and U/u respectively.
        S1 and S2 resolves U/u's remote endpoint with V/v and then install SID S1:: 
        for U/u in FIB. S1:: will not appear in the packet from E/e to 
        U/u over the wire.</t>

        <t>As S1 adopts local N6DN for D1, N3RAN in S1 decapsulates GTP-U 
        packets from V/v to X and then lookup the inner packets from U/u in N6DN
        after the decapsulation.
        </t>

        <dl newline="false" spacing="normal" indent="6">
          <dt>Note: </dt>
          <dd>When the above configurations have been done, 
          MUP is applied only to the packets from/to U/u. 
          Each endpoint in U/u, W/w and E/e can communicate through S1 and S2.
          The rest of traffic from/to other UEs go through the usual 3GPP
          5G user plane path using UPF via S3.</dd>
        </dl>

      </section>

      <section anchor="deploy3" numbered="true" toc="default">
        <name>Adding Direct Segment with New MUP PE </name>

        <t>Another case shown in <xref target="fig_deploy3"/> is that 
        S4 joins the SR network and accommodates edge servers in 
        the N6DN in S4.</t>

        <figure anchor="fig_deploy3" title="">
          <artwork align="center" type="" alt=""><![CDATA[
                         U1
                          |
U/u                       v                       __
  \__ N3   /-----------+-----+------------\      /  \
  /  \RAN /            |MUP-C|             \  __/W/w \
 / V/v\_  |            +-----+        +----|_/N6\    /
 \    / \ |----+                      | S2 |  DN \__/
  \__/   \| S1 |                      +----|      __
   __    /|----+                      +----|_    /  \
  /  \__/ |             +----+        | S4 | \__/E/e \
 /    \N6 \             | S3 |        +----/  N6\    /
 \    /DN  \------------+----+------------/   DN \__/
  \__/             N3UPF  /\ N6UPF
                     X/x /  \ Y/y
                       +-----+
                       | UPF |
                       +-----+
            ]]></artwork>
        </figure>

        <t>The following routing instances are configured:</t>

        <ul>
          <li>N3RAN in S1 (same with the previous case)</li>
          <li>
              <ul>
                <li>export route V/v with RT C1</li>
                <li>import routes which have RT C1 and C2</li>
              </ul>
          </li>
        </ul>

        <ul>
          <li>N6DN in S1</li>
          <li>
            <ul>
              <li>export no route</li>
              <li>import routes which have RT C4</li>
            </ul>
          </li>
        </ul>

        <ul>
          <li>N6DN in S2 (same with the previous case)</li>
          <li>
            <ul>
              <li>export route W/w with RT C4</li>
              <li>import routes which have RT C3 and C4</li>
            </ul>
          </li>
        </ul>

        <ul>
          <li>N3UPF in S3 (same with the previous case)</li>
          <li>
            <ul>
              <li>export route X/x with RT C2</li>
              <li>import routes which have RT C1</li>
            </ul>
          </li>
        </ul>

        <ul>
          <li>N6UPF in S3 (same with the previous case)</li>
          <li>
            <ul>
              <li>export route Y/y with RT C3</li>
              <li>import routes which have RT C4</li>
            </ul>
          </li>
        </ul>

        <ul>
          <li>N6DN in S4</li>
          <li>
            <ul>
              <li>export route E/e with RT C4</li>
              <li>import routes which have RT C3 and C4</li>
            </ul>
          </li>
        </ul>

        <t>Here, the PEs are configured to enable MUP as following:</t>

        <ul>
          <li>S1 (same with the previous case)</li>
          <li>
            <ul>
              <li>advertises Interwork type route: V/v with SID S1::</li>
              <li>set S1:: behavior End.M.GTP4.E or End.M.GTP6.E</li>
            </ul>
          </li>
        </ul>

        <ul>
          <li>S1</li>
          <li>
            <ul>
              <li>advertise Direct type route: MUP Direct Segment community D1 for the local N6DN</li>
              <li>set S1:1:: behavior End.DT4 or End.DT6 for the N6DN in S1</li>
            </ul>
          </li>
        </ul>

        <ul>
          <li>S2 (same with the previous case)</li>
          <li>
            <ul>
              <li>advertise Direct type route: MUP Direct Segment community D1 and SID S2::</li>
              <li>set S2:: behavior End.DT4 or End.DT6 for the N6DN in S2</li>
            </ul>
          </li>
        </ul>

        <ul>
          <li>S4</li>
          <li>
            <ul>
              <li>advertise Direct type route: MUP Direct Segment community D2 and SID S4::</li>
              <li>set S4:: behavior End.DT4 or End.DT6 for the N6DN in S4</li>
            </ul>
          </li>
        </ul>

        <t>As in the previous case, S1 adopts the local N6DN for D1 as long as S1 prioritizes 
        the closer segment for the same MUP Direct Segment. The Direct type route from S4 for D2 
        with SID S4:: will be kept in S1.</t>

        <ul>
          <li>MUP-C (same with the previous case)</li>
          <li>
            <ul>
              <li>attach the MUP Direct Segment ID D1 and RT C3 to the DN in U1</li>
              <li>transforms UE's prefix U/u, the F-TEID on access side (gNB) and QFI in U1 to the ST1 route 
              for the prefix U/u with the F-TEID, the QFI, and RT C3</li>
              <li>transforms F-TEID on core side (UPF) X in U1 
              to the ST2 route for X with MUP Direct Segment community D1 and RT C2</li>
            </ul>
          </li>
        </ul>

        <t>Then N3RAN and N6DN import route X and U/u respectively.
        S2 and S4 resolve U/u's remote endpoint with V/v and then install SID S1:: 
        for U/u in FIB.</t>

        <t>As in the previous case, S1 adopts local N6DN for D1, 
        N3RAN in S1 decapsulates GTP-U packets from V/v to X and then 
        lookup the inner packets from U/u in N6DN after the decapsulation.
        </t>
        <t>For D2 on the other hand, no corresponding N6DN existed in S1. 
        However, E/e with RT C4 from S4 is imported into N6DN in S1 as a 
        VPN route, E/e is reachable from U/u via N6DN for D1 in S1.</t>

        <t>If a session U1' includes the DN corresponding to D2, MUP-C advertises
        ST2 route X' with MUP Direct Segment community D2, and then
        N3RAN in S1 instantiates H.M.GTP4.D or End.M.GTP6.D for X with S4::
        as the last SID in the received Direct type route from S4.
        </t>

        <dl newline="false" spacing="normal" indent="6">
          <dt>Note: </dt>
          <dd>When the above configurations have been done, 
          MUP is applied only to the packets from/to U/u. 
          Each endpoint in U/u, W/w and E/e can communicate through S1, S2 
          and S4. 
          The rest of traffic from/to other UEs go through the usual 3GPP
          5G user plane path using UPF via S3.</dd>
        </dl>

      </section>

      <section anchor="collupsed" numbered="true" toc="default">
        <name>Collapsed MUP PE Deployment</name>

        <t>In this case only S1 enables MUP in a collapsed fashion.
        S2 and S3 are L3VPN PEs without MUP capability. In this section,
        S2 and S3 are illustrated as SRv6 nodes. But they can be 
        non-SR nodes if S1 provides SR independent connectivity to
        S2 and S3.</t>

        <figure anchor="fig_deploy4" title="">
          <artwork align="center" type="" alt=""><![CDATA[
                         U1
                          |
U/u                       v
  \__ N3   /-----------+-----+------------\
  /  \RAN /            |MUP-C|             \
 / V/v\_  |            +-----+             | N6   __
 \    / \ |----+                      +----| DN  /  \
  \__/   \| S1 |                      | S2 |----/W/w \
   __    /|----+                      +----|    \    /
  /  \__/ |             +----+             |     \__/
 / E/e\N6 \             | S3 |             /
 \    /DN  \------------+----+------------/
  \__/             N3UPF  /\ N6UPF
                     X/x /  \ Y/y
                       +-----+
                       | UPF |
                       +-----+
            ]]></artwork>
        </figure>

        <t>The difference between the previous case in <xref target="deploy1"/> 
        for the routing instance configuration is following:</t>

        <ul>
          <li>N6DN in S1</li>
          <li>
            <ul>
              <li>export route E/e with RT C4</li>
              <li>import routes which have RT C3, C4 and C5</li>
            </ul>
          </li>
        </ul>

        <t>Here, S1 is configured to enable MUP and S2 as an L3VPN PE is configured as follows:</t>

        <ul>
          <li>S1</li>
          <li>
            <ul>
              <li>may not advertise Interwork type discovery route for V/v</li>
              <li>may not advertise Direct type discovery route with MUP Direct Segment community D1 and S1:1::</li>
              <li>set S1:1:: behavior End.DT4 or End.DT6 for the N6DN in S1</li>
            </ul>
          </li>
        </ul>

        <ul>
          <li>S2</li>
          <li>
            <ul>
              <li>set S2:: behavior End.DT4 or End.DT6 for the N6DN in S2</li>
            </ul>
          </li>
        </ul>

        <t>Now, session information U1 is added to the MUP Controller, MUP-C, 
        and MUP-C and S1 is configured to transform U1 to the routes as follows:</t>

        <ul>
          <li>MUP-C</li>
          <li>
            <ul>
              <li>attach the MUP Direct Segment ID D1 and RT C5 to the DN in U1</li>
              <li>transforms UE's prefix U/u, the F-TEID on access side (gNB) and QFI in U1 to the ST1 route 
              for the prefix U/u with the F-TEID, the QFI, and RT C5</li>
              <li>transforms F-TEID on core side (UPF) X in U1 
              to the ST2 route for X with MUP Direct Segment community D1 and RT C2</li>
            </ul>
          </li>
        </ul>

        <ul>
          <li>S1</li>
          <li>
            <ul>
              <li>advertises U/u as an L3VPN route with RT C4 and SID S1:1::, 
              when the ST1 route is imported into the N6DN</li>
            </ul>
          </li>
        </ul>

        <t>Then the N3RAN and N6DN import route X and U/u respectively.
        S1 resolves U/u's remote endpoint with V/v and then create the corresponding
        GTP encap entry for U/u into the N3RAN FIB.
        S2 will create a regular L3VPN routing entry for U/u with SID S1:1:: in the N6DN
        when S2 imports the L3VPN route with RT C4 for U/u advertised from S1.</t>

        <t>As S1 adopts local N6DN for D1, N3RAN in S1 decapsulates GTP-U 
        packets from V/v to X and then lookup the inner packets from U/u in N6DN
        after the decapsulation.
        </t>

        <dl newline="false" spacing="normal" indent="6">
          <dt>Note: </dt>
          <dd>When the above configurations have been done, 
          MUP is applied only to the packets from/to U/u. 
          Each endpoint in U/u, W/w and E/e can communicate through S1 and S2.
          The rest of traffic from/to other UEs go through the usual 3GPP
          5G user plane path using UPF via S3.</dd>
        </dl>

      </section>


    </section>


   <section anchor="IANA" numbered="true" toc="default">
      <name>IANA Considerations</name>
      <t>This memo includes no request to IANA.</t>
    </section>
    <section anchor="Security" numbered="true" toc="default">
      <name>Security Considerations</name>
      <t>TBD.</t>
    </section>

    <!-- End section "Contributors" -->

  </middle>
  <!--  *****BACK MATTER ***** -->

 <back>
    <!-- References split into informative and normative -->

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      <references>
        <name>Normative References</name>
        <!--?rfc include="http://xml.resource.org/public/rfc/bibxml/reference.RFC.2119.xml"?-->
            &rfc7333;
            &rfc8402;
            &rfc8986;
            <!-- &I-D.ietf-spring-segment-routing-policy; -->

     <reference anchor="RFC2119" target="https://www.rfc-editor.org/info/rfc2119" xml:base="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.2119.xml">
          <front>
            <title>Key words for use in RFCs to Indicate Requirement Levels</title>
            <seriesInfo name="DOI" value="10.17487/RFC2119"/>
            <seriesInfo name="RFC" value="2119"/>
            <seriesInfo name="BCP" value="14"/>
            <author initials="S." surname="Bradner" fullname="S. Bradner">
              <organization/>
            </author>
            <date year="1997" month="March"/>
            <abstract>
              <t>In many standards track documents several words are used to signify the requirements in the specification.  These words are often capitalized. This document defines these words as they should be interpreted in IETF documents.  This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.</t>
            </abstract>
          </front>
        </reference>
      </references>
      <references>
        <name>Informative References</name>
        <!-- Here we use entities that we defined at the beginning. -->
            <!-- &I-D.ietf-mpls-mna-fwk;-->
            &rfc4360;
            &rfc4684;
            &rfc5213;
            &rfc8885;
            &rfc9433;


        <reference anchor="TS.23501" target="http://www.3gpp.org/ftp/Specs/html-info/23501.htm">
            <front>
                <title>System architecture for the 5G System (5GS)</title>
                <author>
                    <organization>3GPP</organization>
                </author>
                <date day="24" month="September" year="2021"/>
            </front>
            <seriesInfo name="3GPP TS" value="23.501 17.2.0" />
        </reference>
      </references>
    </references>

    <!-- Filled after when substantial contributions are made: -->

    <section anchor="Acknowledgements" numbered="false">
      <name>Acknowledgements</name>
      <t>The authors would like to thank Jeffrey Zhang,
      Keiichi Makizono, Hideyuki Sasaki, Teruyuki Oya, 
      Yoichi Funabiki, Daisuke Koshiro, Derek Yeung,
      Kalyani Rajaraman, Csaba Keszei, Daiki Kijima,
      Ryuma Seno, Keiji Hara, Mikio Nakajima, Masayuki Yamazaki,
      Takuto Shiozawa, Manabu Mikami, Takaya Watanabe,
      Hidenori Aita, Hiroyuki Fukumori, Leo Fujita, 
      Toshihiro Yokomine, Toshikazu Morioka, Yadav Rituraji,
      Junya Yoshino, Takayuki Koshikawa,
      Kazunari Nagai, Tadayuki Okuda, Takahiro Hara,
      Yuya Kusakabe, Takeru Hayasaka,
      Hideki Takase, Yutaka Kikuchi, Kazuma Nishiuchi,
      Mitsuhiro Osaki, Suresh Krishnan, Sri Gundavelli,
      Zafar Ali, Luay Jalil, Markus Amend, Marco Liebsch, 
      and Lionel Morand for their reviews and discussions with the authors.</t>
    </section>
    <!-- Possibly a 'Contributors' section ... -->

    <section numbered="false">
      <name>Contributors</name>
      <contact fullname="Clarence Filsfils">
        <organization>Cisco Systems, Inc.</organization>
        <address>
          <postal>
            <street/>
            <city/>
            <region/>
            <code/>
            <country>Belgium</country>
          </postal>
          <email>cf@cisco.com</email>
        </address>
      </contact>
      <contact fullname="Ketan Talaulikar" initials="K." surname="Talaulikar">
        <organization>Cisco Systems</organization>
        <address>
          <postal>
            <street/>
            <city/>
            <region/>
            <code/>
            <country>India</country>
          </postal>
          <email>ketant.ietf@gmail.com</email>
        </address>
      </contact>
    </section>

    <section numbered="false">
      <name>Additional Authors</name>

      <contact fullname="Ashiq Khan" initials="A." surname="Khan">
        <organization>SoftBank</organization>
        <address>
          <postal>
            <street/>
            <city/>
            <region/>
            <code/>
            <country>Japan</country>
          </postal>
          <email>ashiq.khan@g.softbank.co.jp</email>
        </address>
      </contact>
      <contact fullname="Miya Kohno" initials="M." surname="Kohno">
        <organization abbrev="Cisco Systems, Inc.">
              Cisco Systems, Inc.</organization>
        <address>
          <postal>
            <street/>
            <city/>
            <region/>
            <code/>
            <country>Japan</country>
          </postal>
          <email>mkohno@cisco.com</email>
        </address>
      </contact> 
      <contact fullname="Teppei Kamata" initials="T." surname="Kamata">
        <organization abbrev="Cisco Systems, Inc.">
              Cisco Systems, Inc.</organization>
        <address>
          <postal>
            <street/>
            <city/>
            <region/>
            <code/>
            <country>Japan</country>
          </postal>
          <email>tkamata@cisco.com</email>
        </address>
      </contact> 
      <contact fullname="Pablo Camarillo Garvia" initials="P." surname="Camarillo">
        <organization abbrev="Cisco Systems, Inc.">
              Cisco Systems, Inc.</organization>
        <address>
          <postal>
            <street/>
            <city/>
            <region/>
            <code/>
            <country>Spain</country>
          </postal>
          <email>pcamaril@cisco.com</email>
        </address>
      </contact> 
      <contact fullname="Daniel Voyer" initials="D." surname="Voyer">
        <organization abbrev="Bell Canada">Bell Canada</organization>
        <address>
          <postal>
            <street></street>
            <city></city>
            <region></region>
            <code></code>
            <country>Canada</country>
          </postal>
          <email>daniel.voyer@bell.ca</email>
        </address>
      </contact>
      <contact fullname="Shay Zadok" initials="S." surname="Zadok">
        <organization abbrev="Broadcom">
              Broadcom</organization>
        <address>
          <postal>
            <street/>
            <city/>
            <region/>
            <code/>
            <country>Israel</country>
          </postal>
          <email>shay.zadok@broadcom.com</email>
        </address>
      </contact> 
      <contact fullname="Israel Meilik" initials="I." surname="Meilik">
        <organization abbrev="Broadcom">
              Broadcom</organization>
        <address>
          <postal>
            <street/>
            <city/>
            <region/>
            <code/>
            <country>Israel</country>
          </postal>
          <email>israel.meilik@broadcom.com</email>
        </address>
      </contact> 
      <contact fullname="Ashutosh Agrawal" initials="A." surname="Agrawal">
        <organization abbrev="Intel">
              Intel</organization>
        <address>
          <postal>
            <street/>
            <city/>
            <region/>
            <code/>
            <country>USA</country>
          </postal>
          <email>ashutosh.agrawal@intel.com</email>
        </address>
      </contact> 
      <contact fullname="Kumaresh Perumal" initials="K." surname="Perumal">
        <organization abbrev="Intel">
              Intel</organization>
        <address>
          <postal>
            <street/>
            <city/>
            <region/>
            <code/>
            <country>USA</country>
          </postal>
          <email>kumaresh.perumal@intel.com</email>
        </address>
      </contact> 
    </section>

    <!-- Change Log

v00 2021-10-08  Matsushima   Skelton version
    -->
 </back>
</rfc>
