RTG Working Group                                          K. Majumdar
Internet Draft                                               Microsoft
Intended status: Informational                             U. Chunduri
Expires: October 12, 2024                                        Intel
                                                             L. Dunbar
                                                             Futurewei
                                                    September 12, 2023


          Extension of Transport Aware Mobility in Data Network
              draft-mcd-rtgwg-extension-tn-aware-mobility-08

Abstract
   The existing Transport Network Aware Mobility for 5G (TN-AWARE-
   MOBILITY) specifies a framework for mapping the 5G mobile systems'
   Slice and Service Types (SSTs) to corresponding underlying network
   paths to ensure the desired QoS for the services.The focus of (TN-
   AWARE-MOBILITY) is limited to the 3GPP domain and doesn't cover the
   network for user plane traffic between the UPFs and the services
   hosted in data centers.

   This document describes the mechanisms to achieve the same QoS for
   the mobility traffic from the 3GPP domain to the service
   destinations over the IP Data Networks. Extending the QoS guarantee
   for the SSTs to the data centers where the services are hosted
   becomes necessary to maintain the end-to-end QoS for data plane
   traffic between UEs and their corresponding service destinations.

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), its areas, and its working groups.  Note that
   other groups may also distribute working documents as Internet-
   Drafts.

   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."




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   The list of current Internet-Drafts can be accessed at
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   This Internet-Draft will expire on April 23, 2021.

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Table of Contents


   1. Introduction...................................................3
   2. Conventions used in this document..............................3
   3. Extending 5G SSTs QoS to Data Network..........................4
   4. Mobility Packets Transition to the Data Network................5
   5. Transport Network Characteristics Mapping to TE Paths..........8
   6. Extend TN Aware Mobility via BGP SR-TE Policy..................9
      6.1. TN Aware Mobility Policy Encoding........................11
      6.2. Operations of Applying the TN Aware Mobility Policy......12
   7. TN Aware Mobility Policies Distribution via PCE Controller....12
   8. TN Aware Mobility Policies via NETCONF/RestConf/gRPC..........13
   9. Extend BGP FlowSpec for TN Aware Mobility.....................14
   10. Mapping of TN Characteristics on SD-WAN Edge Node............14
   11. IANA Considerations..........................................16
   12. Security Considerations......................................16
   13. Contributors.................................................16
   14. References...................................................16
      14.1. Normative References....................................16


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      14.2. Informative References..................................17
   15. Acknowledgments..............................................18
   Authors' Addresses...............................................19


1. Introduction

   The [TN-AWARE-MOBILITY] describes the mapping of 5G slices to IP or
   Layer 2 transport network for both control plane and data plane
   traffic across back-haul, mid-haul, and front-haul segments within
   the 3GPP domain [TS.23.501-3GPP]. While the 5G control plane traffic
   is end-to-end from UEs, gNB, to the 3GPP specified control functions
   (such as Session Management function, Access and Mobility Management
   Function, etc.), the data plane traffic management limited to UEs<->
   gNB <-> UPFs (user plane functions) is not end-to-end.

   As 5G services are processed by their corresponding servers in data
   centers through the IP network, achieving the desired QoS for the
   data plane traffic between gNBs <-> UPFs by mapping to the
   appropriate underlay IP networks is insufficient to ensure the end-
   to-end QoS. This draft describes the mechanisms for extending the 5G
   Service Slices mapping enforced within the 3GPP domain to the
   appropriate IP underlays from UPFs to 5G service destinations,
   including RSVP-TE[RFC3209], SRv6[RFC8986], MPLS-TE[RFC3812], and
   Preferred Path Routing (PPR) [RTG-PPR].  The goal is to ensure the
   end-to-end QoS guarantee for the 5G service slices.

   Note: even though the 3GPP domain has underlay data networks
   connecting various 3GPP specified functions, the term Data Network
   in this document represents the IP data network outside the 3GPP
   domain, a.k.a. the N6 interface described in [UPlane-5G-ANA].

2. Conventions used in this document

   BSID       - Binding SID

   DC         - Data Center

   DN         - Data Network [TS.23.501-3GPP]

   EMBB       - enhanced Mobile Broadband [TS.23.501-3GPP]



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   gNB        - Next Generation NodeB [TS.23.501-3GPP]

   GTP-U      - GPRS Tunneling Protocol - User Plane [TS.23.501-3GPP]

   MIOT       - Massive IOT [TS.23.501-3GPP]

   PECP       - Path Computation Element (PCE) Communication Protocol

   SD-WAN     - Software-Defined Wide Area Network

   SID        - Segment Identifier

   SLA        - Service Layer Agreement

   SST        - Slice and Service Types [TS.23.501-3GPP]

   SR         - Segment Routing

   SR-PCE     - SR Path Computation Element

   UE         - User Equipment

   UPF        - User Plane Function [TS.23.501-3GPP]

   URLLC      - Ultra reliable and low latency communications
               [TS.23.501-3GPP]


3. Extending 5G SSTs QoS to Data Network

  In actual deployment, a UPF can be connected to a C-PE node that
  ingresses to the IP network (i.e., the N6 Interface of the 3GPP
  domain) or embedded with the C-PE function. The C-PE node can be an
  SD-WAN [NET2CLOUD] edge node, L2/L3 VPN [RFC4364] edge node, or SR-
  TE [RFC8402] edge node. For the enterprise 5G scenario, the L3
  aggregator function can be integrated with the UPFs for all the
  enterprise's 5G mobility connections.

  The proposed mechanisms to extend the 5G SSTs QoS in the Data
  Network focuses on the following areas:



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  a) The Mobility packets transition in and out from the UPFs to the C-
     PEs node maintaining the same transport path characteristics.

  b) On a C-PE node, based on the transport characteristics, use
     different methods of fetching TE (traffic engineered) path
     segments from the IP network controller and map the TE path
     segments to the packets from UEs.

  c) On an SD-WAN CE Node, based on the transport characteristics,
     mapping of UP packets to the secure and un-secure tunnel paths
     based on 5G service policies.

  Figure 1 under Section 4 depicts data from UEs through the UPFs and
  C-PEs to the service destinations. In some cases, UPF is integrated
  with the C-PE functions.

4. Mobility Packets Transition to the Data Network

   As a mobility packet transitioning from the UPF to the C-PE node,
   the GTP header is decapsulated, i.e., the UDP port number carried by
   the GTP header as specified by the [TN-AWARE-MOBILITY] is no longer
   present in the packet. Here are some approaches to classify the
   mobility packets when transitioning to the Data Network so that the
   appropriate policies can be applied to achieve the same QoS as the
   3GPP domain:
   A) When the UPF is connected to a C-PE via a direct link (Figure 1
   below), the respective application controller needs to pass the
   desired QoS policy information to the Data Network's management
   system (DN Mgnt) and the 5G Management Plane (NSSMF) [TS.23.501-
   3GPP]. In Some deployments, the application controller, 5G NSSMF,
   and DN Mgnt belong to one operator. In some deployments, they are
   separate entities, thus requiring contract binding for the desired
   QoS.

   The C-PE can encapsulate the mobility packet from the UPF with
   another outer IP header, with the destination address of the outer
   header set to the service destination hosted in a remote data center
   and the source UDP port number set as [TN-AWARE-MOBILITY. Here is
   the packet illustration:

   - From the UPF to the C-PE Node:
     Inner IP Hdr (UE Packet) + Transport Hdr (Carrying UDP Src Port)
     + Outer IP (C-PE Node Address)


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   - From the C-PE to the UPF Node:
     Outer IP (UPF Node Address) + Transport Hdr (Carrying UDP Src
     Port) + Inner IP Hdr (UE Packet)

   B) When the 5G Core and the IP Data Network (N6 interface) are
   managed by one operator, a UPF can have the embedded C-PE function
   (Scenario B of Figure 1). Under this scenario, the original UDP
   Source Port information can be used to select the underlays for
   reaching the service destinations based on the local policy.







































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     Scenario A:

                          +--(AppCtrl)----+
                          |               |
                       +--+-----+      +--+---+
                       | 3GPP   |      | IP DN|
                       | NSSMF  |      | Mgnt |
                       +----V---+      +--V--+
                            |           |
             +----+       +--+--+       +--+--+
      UE-----| gNB|-------| UPF |-------| C-PE|------DN
             +----+       +-----+       +-- --+

             |--- N3 OR N9 -----||---- N6 -----

       |------- Mobile Network--||---- IP Data Network ----|



     Scenario B:
                           (AppCtrl)
                                |
                       +--------+------+
                       | 3GPP   |IP DN |
                       | NSSMF  | Mgnt |
                       +--------+------+
                                |
          +-----------+      +--+---+
           |           |      |      |
      UE---| gNB-CU(UP)|------| UPF +|--------DN-------
           |           |      | C-PE |
           +-----------+      +------+

                   |- N3 OR N9 -||----N6 -------------|

      |------ Mobile Network ---||-- IP Network-------|

            Figure 1: Mobile and IP Data Network for UE



     Figure 2 illustrates the TN Aware Mobility packet format under
     scenario A.







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    - UE Packet format in the Mobile Network from gNB to the UPF:

       +---------+----------+-------+------------+----------+
       | UE Data | Inner IP | GTP-U | UDP Header | Outer IP |
       +---------+----------+-------+------------+----------+



    - UE Packet format in the IP Network to the Ingress C-PE Node:

       +---------+----------+------------------+------------+
       | UE Data | Inner IP | Transport Header | C-PE Header|
       +---------+----------+------------------+------------+

          Figure 2: UE Packet Transition from Mobile to IP Network

   The source port in the original UDP header indicates the TN Aware
   Mobility SST type.

5. Transport Network Characteristics Mapping to TE Paths

   Within the 5G Core [TS.23.501-3GPP], UE traffic is carried by the
   GTP tunnels terminated by the UPFs. [TN-AWARE-MOBILITY] specifies
   using the GTP header's source UDP port number to indicate the
   desired transport network characteristics. The same transport
   network characteristics should be carried through the IP data
   network to the destinations to maintain the end-to-end SLA for the
   UE traffic.

   3GPP specifies that the User Plane Function (UPF) decapsulates the
   GTP header and hands the inner payload to the N6 interface. As more
   and more deployments have integrated UPF with the ingress routing
   functions to the IP data network, it is relatively easy to carry the
   UDP port information from the GTP header into the IP data network,
   e.g.,

 - Carry the UDP port number in an extra IP encapsulation (VxLAN,
   GENEVE, etc.) to the IP network, or,
 - Assign an identifier in the header to the IP networks based on the
   UDP port number in the GTP header.

   Here are some options in passing the corresponding policies:





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   Option 1: Assume the ingress C-PE is connected to a BGP SR-TE
   Controller through a BGP SR-TE Policy SAFI Session. Section 6
   describes the mechanism to map mobility traffic to the BGP SR-TE
   Underlay Path Segments based on the mobility transport
   characteristics:

   Option 2: Assume the ingress C-PE is connected to the PCE (Path
   Compute Element) Controller through a PCEP Session, which can pass
   the policy to map mobility traffic to the TE underlay paths
   [RFC9168] based on the mobility transport characteristics.

   Option 3: Assume the ingress C-PE is connected to the TE Controller
   over NETCONF/Restconf/ Netconf or gRPC session. The existing
   mechanism would be used to download the TE Underlay Path Segments to
   the C-PE node based on the mobility transport characteristics.

   Option 4: Assume the ingress C-PE is connected to the BGP SR
   FlowSpec Controller through a BGP FlowSpec session. The FlowSpec
   Redirect to indirection-id Extended community [FLOWSPEC-PATH-
   REDIRECT] can be used to map the Mobility Transport Path
   Characteristics to SR Traffic rules. [FLOWSPEC-TN-MOBILITY]
   specifies BGP FlowSpec extension to disseminate the policies from 5G
   mobile networks so that the 5G mobile systems slices and Service
   Types (SSTs) can be mapped to optimal underlying network paths in
   the data network.

6. Extend TN Aware Mobility via BGP SR-TE Policy

  To integrate the 5G Core's transport aware mobility policies with
  BGP SR-TE Policy at the Ingress C-PE UPF, a class map needs to be
  defined to classify the incoming mobility traffic with different
  transport path characteristics.

  Assume that the ingress C-PE (embedded in UPF) support the BGP SR-TE
  Policy SAFI [BGP-SR-TE-POLICY] and the BGP SR-TE Controller can
  compute the SR segments that can satisfy the SLA for the transport
  characteristics identified by the 5G UDP SRC Port Range based on the
  [TN-AWARE-MOBILITY] draft.

   The figure below captures the overall topology and how to map the
   mobility traffic on the Ingress C-PE, which has the BGP SR-Policy
   SAFI connection with the BGP SR-TE Controller:






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                         +-----------+   +----+{UDP Src Port Range}
                         | BGP SR-TE |-->| Map|       <-->
                         | Controller|   | DB |{BGP SR-TE Policy }
                         +-----------+   +----+
                           /
                          /
                         /
                        /
                       /                              +--------+
                      / BGP SR-TE Policy with         |IOT Data|
                     /  Mobility-Policy-Transition    +--------+
                    /                                       /Public
                   /                                  mIoT / Cloud
                  /                                  +----+
             +------+  Policy1: UDP Src Port Xx-Xy   |
             |      A1-------------------------------+
             |      |  Policy2: UDP Src Port Yx-Yy    URLLC
     UE------| UPF  A2-------------------------------------
             | +PE1 |  Policy3: UDP Src Port Zx-Zy
             |      A3------------------------------+
             |      |                                \
             +------+                                 +----+
     {UDP Src Port Num# <--> SR Policy N}              eMBB \
                                                             \
                                                         +--------+
                                                         | Content|
                                                         +--------+
                                                          Private DC
                  ---------->
       +------+----------+-------+-----+----------+
       | Data | Inner IP | GTP-U | UDP | Outer IP |
       +------+----------+-------+-----+----------+

                                      ---------->
                     +------+----------+-------------+
                     | Data | Inner IP |   SR Header |
                     +------+----------+-------------+

  Figure 3: TN Aware Mobility Traffic Mapping to BGP SR-TE Policy Path

   Note that, the SR Header in the figure above is shown as an
   illustrative purpose and the actual outgoing packet format is based
   on the BGP SR-TE mechanism (SR-MPLS or SRv6). If the BSID is not
   present with the BGP SR-TE Policy, the local ingress C-PE will map
   the incoming traffic to the best effort policy map path in the
   underlay.





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6.1. TN Aware Mobility Policy Encoding

   Mobility-Policy-Transition Sub-TLV specified here is to maintain the
   policy in the SR-TE network consistent with the 5G Core for the
   selective mobility traffic. The Mobility-Policy-Transition Sub-TLV
   is one of the Sub-TLVs under the Tunnel Type = 15 (SR Policy) under
   the SR-TE Policy NLRI [BGP-SR-TE-POLICY] sent to the relevant
   ingress C-PEs.

   SR Policy SAFI NLRI: <Distinguisher, Policy-Color, Endpoint>
   Attributes:
     Tunnel Encapsulation Attribute (23)
     Tunnel Type: SR Policy (15)
       {other SR policies Sub-TLVs specified in [BGP-SR-TE-POLICY]
       Mobility-Policy-Transition Sub-TLV

   Suppose a mobility service has multiple instances reachable from
   different SR egress routers. In that case, the SR-TE controller
   might need to send multiple SR-TE policies, each with one of those
   egress addresses in the "Endpoint" field.

   The Mobility-Policy-Transition Sub-TLV is optional, only applicable
   to the mobility traffic whose destinations match with the prefixes
   in the SR Policy NLRI. It MUST NOT appear more than once in the SR-
   TE Policy.

 0                   1                   2                   3
 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|      Type     |    Sub-Type   |     Length    |     Flags     |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|    UDP Src Port Start Value   |    UDP Src Port End Value     |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         Mobility-Policy-Transition Sub-TLV

     where:
       - Type = Mobility-Policy-Transition: TBD1 by IANA.
       - Sub-Type: This field has one of the following values:
              0: Reserved.
              1: UDP Source Port Range.
              2 - 255: Reserved for future use.
       - Length: 6 octets.



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       - Flags: 1 octet of flags.  None are defined at this stage.
          Flags SHOULD be set to zero on transmission and MUST be
          ignored on receipt.
       - UDP Src Port Start Value: 2 octets value to define the
          staring of the value of the UDP Src Port range.
       - UDP Src Port End Value: 2 octets value to define the end
          value of the UDP Src Port range.

6.2. Operations of Applying the TN Aware Mobility Policy

  The TN Aware Mobility Policy might be based on something other than
  the destination or source addresses of the packets from/to UEs
  because the 5G's Session Controller manages the UE traffic on a
  finer granularity than the IP addresses. In this case, the BGP
  UPDATE with the SR-TE Policy SAFI doesn't include the top-level NLRI
  [RFC4271], which means that the policy specified by the Mobility-
  Policy-Transition Sub-TLV applies to all the mobility traffic from
  the 5G N6 Interface (i.e., from the UPFs).

  When the TN Aware Mobility Policy is based on UE traffic's
  destination addresses, the BGP UPDATE with the SR-TE Policy SAFI
  includes the top-level NLRI [RFC4271], which means that the policy
  specified by the Mobility-Policy-Transition Sub-TLV only applies to
  the mobility traffic with destinations specified in the top-level
  NLRI [RFC4271] from the 5G N6 Interface (i.e., from the UPFs).

  The ingress nodes compare all the BGP UPDATE messages for the routes
  and the SR-TE policies sent from the controller per procedure
  described by [RFC9256].

7. TN Aware Mobility Policies Distribution via PCE Controller

  To achieve the desired QoS for the mobility traffic via the PCE
  Controller, the Ingress C-PE, standalone or embedded within the UPF,
  is assumed to support the PCEP communication (PCEP) protocol with
  the PCE Controller.

  The PCE controller must have the mapping of the mobility traffic
  from the GTP tunnels [TS.23.501-3GPP] with the desired transport
  path characteristics.



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   [RFC9168] specifies using the BGP's Flow Specification Rules for
   IPv4 [RFC8955] and IPv6 [RFC8956] in PCE Communication Protocol
   (PCEP). Section 9 of this document specifies the mechanism of using
   UDP Source port filtering in the BGP FlowSpec.

8. TN Aware Mobility Policies via NETCONF/RestConf/gRPC

   Assume that the Ingress C-PE UPF has Restconf or gRPC connection
   with the TE Controller, the source UDP port YANG Data Model of the
   [RFC8519] can be utilized to pass the allowed source UDP ports.

   Here is an example using the [RFC8519] specified YANG Data Model:

   <?xml version="1.0" encoding="UTF-8"?>
     <config xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
       <acls
       xmlns="urn:ietf:params:xml:ns:yang:ietf-access-control-list">
          <acl>
            <name>sample-port-acl</name>
            <type>ipv4-acl-type</type>
            <aces>
              <ace>
                <name>rule1</name>
                <matches>
                  <udp>
                    <source-port>
                      <lower-port>16384</lower-port>
                      <upper-port>16387</upper-port>
                    </source-port>
                  </udp>
                </matches>
                <actions>
                  <forwarding>[TE-Policy]</forwarding>
                </actions>

              </ace>
            </aces>
        </acl>
       </acls>
      </config>




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   Note: Need to search TE YANG modules to find one that includes the
   ACTION of selecting the specified "TE-Policy".

9. Extend BGP FlowSpec for TN Aware Mobility

   [FlowSpec-TN-Aware] specifies a BGP Flow Specification (FlowSpec)
   extension to disseminate the policies from 5G mobile networks so
   that the 5G mobile systems slices and Service Types (SSTs) can be
   mapped to optimal underlying network paths in the data network
   outside the 5G UPFs which is the N6 interface in 3GPP 5G
   Architecture [3GPP TR 23.501].

10. Mapping of TN Characteristics on SD-WAN Edge Node

   This section specifies a generic approach for SD-WAN Edge Node to
   map the mobility traffic to the appropriate IP data network paths
   based on the policies passed from the 5G Core. The existing [TN-
   AWARE-MOBILITY] draft is extended to support new Transport Path
   Characteristics "Security" for the mobile traffic where security is
   important for specific mobile traffic.

   Based on the UDP Src Port characteristics from the mobile network,
   the SD-WAN edge node can determine which traffic needs to be carried
   by a secure tunnel or an un-secure tunnel where low latency is more
   important than security.






















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  The below figure tries to capture the overall topology, and how to
  map the mobility traffic for Enterprise 5G traffic:


                                 +----------+
                                 |  BGP RR  |
                            +----|Controller|--+
                           /     +----------+   \
                          /                      \      Internet
                         /                        \         |
                        /                          \        |
                       /                            \  URLLC|
                      /                              \      |
                     /                                \     /
            +-------+  MPLS Path: URLLC Traffic   +----+-+ /
            |       A1---------------------------B1      |/   MIOT
            |       |  Secure Path1: MIOT Traffic |      |   +----+
     UE-----| UPF + A2---------------------------B2 C-PE2|---|IOT |
            | C-PE1 |  Secure Path2: EMBB Traffic |      |   +----+
            |       A3---------------------------B3      |\   Public
            |       |                             |      | \  Cloud
            +-------+                             +------+  \
     {UDP Src Port X <--> MPLS}                              \
     {UDP Src Port Y:Security <--> IPSec SA Identifier}  EMBB \
                                                          +-------+
                                                          |Content|
                                                          +-------+
                                                            Public
                                                            Cloud
                  ---------->
       +------+----------+-------+-----+----------+
       | Data | Inner IP | GTP-U | UDP | Outer IP |
       +------+----------+-------+-----+----------+

                                           ---------->
                         +------+----------+--------------+
                         | Data | Inner IP | IPSec Header |
                         +------+----------+--------------+

     Figure 7: Secure TN Aware Mobility Traffic Mapping on SD-WAN Edge

   The SD-WAN Edge Node can map the URLLC traffic without any security
   characteristics to the underlay MPLS path, whereas MIOT, and EMBB
   traffic with security characteristics gets mapped to the underlay
   IPSec Tunnel path. The mapping between SD-WAN overlay and underlay
   routes are described in the [BGP-SDWAN-Discovery] draft.



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   The SD-WAN Edge identifies the incoming mobility traffic
   characteristics using the class-map defined in Section 5.1 and
   selects the appropriate SD-WAN underlay tunnel.

11. IANA Considerations

   No IANA action is needed.

12. Security Considerations

    This document does not introduce any new security issues.


13. Contributors

   The following people have contributed to this document.

   Dhruv Dhody
   Huawei Technologies

   Email: dhruv.ietf@gmail.com


14. References


14.1. Normative References

   [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
             Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC3209] D. Awduche, et al, "RSVP-TE: Extensions to RSVP for LSP
             Tunnels", RFC3209, Dec. 2001.

   [RFC5440] JP. Vasseur, Ed., JL. Le Roux, Ed., "Path Computation
             Element (PCE) Communication Protocol (PCEP)", March 2009.

   [RFC9012] K. Patel, et al, "The BGP Tunnel Encapsulation Attribute",
             April 2021.





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   [RFC8986] c. Filsfils, et al, "Segment Routing over IPv6 (SRv6)
             Network Programming", RFC8986, Feb. 2021.

   [RFC9168] D. Dhody, A. Farrel, Z. Li, "Path Computation Element
             Communication Protocol (PCEP) Extension for Flow
             Specification", RFC9168, Jan. 2022.
14.2. Informative References

   [FlowSpec-TN-Aware] L, Dunbar, K. Majumdar, U. Chunduri, "BGP
   Dissemination of FlowSpec for Transport Aware Mobility", draft-dmc-
   idr-flowspec-tn-aware-mobility-04, July 2023.

   [TN-AWARE-MOBILITY] U. Chunduri, et al, "Transport Network aware
   Mobility for 5G", draft-ietf-dmm-tn-aware-mobility-07, July 2023



   [BGP-SR-TE-POLICY] S. Previdi, et al, "Advertising Segment Routing
   Policies in BGP", draft-ietf-idr-segment-routing-te-policy-23, July
   2023



   [SDWAN-BGP-USAGE] L. Dunber, et al, "BGP Usage for SDWAN Overlay
   Networks", draft-ietf-bess-bgp-sdwan-usage-14, July 2023



   [BGP-SDWAN-Discovery] L. Dunbar, et al, "BGP UPDATE for SDWAN Edge
   Discovery", draft-ietf-idr-sdwan-edge-discovery-10, June 2023



   [FLOWSPEC-PATH-REDIRECT] G. Van de Velde, K. Patel, Z.Li, "Flowspec
             Indirection-id Redirect", draft-ietf-idr-flowspec-path-
             redirect-12, Nov. 2022.

   [FLOWSPEC-TN-MOBILITY] L. Dunbar, K. Majumdar, U. Chunduri, "BGP
             Dissemination of FlowSpec for Transport Aware Mobility",
             draft-dmc-idr-flowspec-tn-aware-mobility-04. July 2023,






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   [RTG-PPR] U. Chunduri, L. Contreras, M. Bhaskaran, J. Tantsura, and
             P. Muley, "Preferred Path Routing Framework", Work in
             Progress, draft-chunduri-rtgwg-preferred-path-routing-03,
             Nov 2022.

   [NET2CLOUD] L. Dunbar, et al, "Dynamic Networks to Hybrid Cloud DCs:
             Problem Statement and Mitigation Practices", draft-ietf-
             rtgwg-net2cloud-problem-statement-29, Aug. 2023.

   [UPlane-Ana-5G] S. Homma, T. Miyasaka, S. Matsushima, and D. Voyer,
             "User Plane Protocol and Architectural Analysis on 3GPP 5G
             System", Work in Progress, draft-ietf-dmm-5g-
             uplaneanalysis-04, 2 November 2020.



15. Acknowledgments

   TBD.

   This document was prepared using 2-Word-v2.0.template.dot.
























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Authors' Addresses

   Kausik Majumdar
   Microsoft

   Email: kmajumdar@microsoft.com

   Uma Chunduri
   Intel Corporation

   Email: umac.ietf@gmail.com


   Linda Dunbar
   Futurewei

   Email: linda.dunbar@futurewei.com





























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