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IPv4 NLRI with IPv6 Next Hop Use Cases
draft-mishra-bess-ipv4nlri-ipv6nh-use-cases-08

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This is an older version of an Internet-Draft whose latest revision state is "Replaced".
Authors Gyan Mishra , Mankamana Prasad Mishra , Jeff Tantsura , Lili Wang , Qing Yang , Adam Simpson , Shuanglong Chen
Last updated 2021-02-22 (Latest revision 2020-11-18)
Replaced by draft-mishra-bess-deplment-guidlin-ipv4nlri-ipv6nh
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draft-mishra-bess-ipv4nlri-ipv6nh-use-cases-08
BESS Working Group                                             G. Mishra
Internet-Draft                                              Verizon Inc.
Intended status: Best Current Practice                         M. Mishra
Expires: August 26, 2021                                   Cisco Systems
                                                             J. Tantsura
                                                            Apstra, Inc.
                                                                 L. Wang
                                                  Juniper Networks, Inc.
                                                                 Q. Yang
                                                         Arista Networks
                                                              A. Simpson
                                                                   Nokia
                                                                 S. Chen
                                                     Huawei Technologies
                                                       February 22, 2021

                 IPv4 NLRI with IPv6 Next Hop Use Cases
             draft-mishra-bess-ipv4nlri-ipv6nh-use-cases-08

Abstract

   As Enterprises and Service Providers upgrade their brown field or
   green field MPLS/SR core to an IPv6 transport such as MPLS LDPv6, SR-
   MPLSv6 or SRv6, Multiprotocol BGP (MP-BGP)now plays an important role
   in the transition of the core from IPv4 to IPv6 being able to
   continue to support legacy IPv4, VPN-IPv4, and Multicast VPN IPv4
   customers.

   This document describes the critical use case and OPEX savings of
   being able to leverage the MP-BGP capability exchange usage as a pure
   transport allowing both IPv4 and IPv6 to be carried over the same BGP
   TCP session.  By doing so, allows for the elimination of Dual
   Stacking on the PE-CE connections making the peering IPv6-ONLY to now
   carry both IPv4 and IPv6 Network Layer Reachability Information
   (NLRI).  This document now provides a solution for IXPs (Internet
   Exchange points) that are facing IPv4 address depletion at these
   peering points to use BGP-MP capability exchange defined in [RFC5549]
   to carry IPv4 (Network Layer Reachability Information) NLRI in an
   IPv6 next hop using the [RFC5565] softwire mesh framework.

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

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   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on August 26, 2021.

Copyright Notice

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

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (https://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Requirements Language . . . . . . . . . . . . . . . . . . . .   6
   3.  eBGP PE-CE IPv4 and IPv6 NLRI over IPv6 Next Hop Peer Use
       Case Interop Testing  . . . . . . . . . . . . . . . . . . . .   6
   4.  RFC 8950 updates to RFC 5549  . . . . . . . . . . . . . . . .   6
   5.  Operational Improvements with Single IPv6 transport peer  . .   8
   6.  Operational Considerations  . . . . . . . . . . . . . . . . .   8
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   9
   8.  Security Considerations . . . . . . . . . . . . . . . . . . .   9
   9.  Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .   9
   10. References  . . . . . . . . . . . . . . . . . . . . . . . . .   9
     10.1.  Normative References . . . . . . . . . . . . . . . . . .   9
     10.2.  Informative References . . . . . . . . . . . . . . . . .  10
   Appendix A.  IPv4 NLRI IPv6 Next Hop Vendor Testing . . . . . . .  12
     A.1.  Router and Switch Vendors Support and Quality Assurance
           Engineering Lab Results.  . . . . . . . . . . . . . . . .  12
     A.2.  Router and Switch Vendors Interoperability Lab Results. .  12
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  13

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1.  Introduction

   As Enterprises and Service Providers upgrade their brown field or
   green field MPLS/SR core to an IPv6 transport such as MPLS LDPv6, SR-
   MPLSv6 or SRv6, Multiprotocol BGP (MP-BGP)now plays an important role
   in the transition of the core from IPv4 to IPv6, and being able to
   continue to support legacy IPv4, VPN-IPv4, and Multicast VPN IPv4
   customers.

   IXPs (Internet Exchange points) are also facing IPv4 address
   depletion at their peering points, which are large Layer 2 transit
   backbones that service providers peer and exchange IPv4 and IPv6
   (Network Layer Reachability Information) NLRI.  Today these transit
   exchange points are dual stacked.  One proposal to solve this issue
   is to use [RFC5549] to carry IPv4 (Network Layer Reachability
   Information) NLRI in an IPv6 next hop and eliminate the IPv4 peering
   completely using the concept of [RFC5565] softwire mesh framework.
   So now with the MP-BGP reach capability exchanged over IPv4 AFI over
   IPv6 next hop peer we can now advertise IPv4(Network Layer
   Reachability Information) NLRI over IPv6 peering using the [RFC5565]
   softwire mesh framework.

   Multiprotocol BGP (MP-BGP) specifies that the set of usable next-hop
   address families is determined by the Address Family Identifier (AFI)
   and the Subsequent Address Family Identifier (SAFI).  Historically
   the AFI/SAFI definitions for the IPv4 address family only have
   provisions for advertising a Next Hop address that belongs to the
   IPv4 protocol when advertising IPv4 or VPN-IPv4 Network Layer
   Reachability Information (NLRI).  [RFC5549] specifies the extensions
   necessary to allow advertising IPv4 NLRI or VPN-IPv4 NLRI with a Next
   Hop address that belongs to the IPv6 protocol.  This comprises an
   extension of the AFI/SAFI definitions to allow the address of the
   Next Hop for IPv4 NLRI or VPN-IPv4 NLRI to also belong to the IPv6
   Protocol.  [RFC5549] defines the encoding of the Next Hop to
   determine which of the protocols the address actually belongs to, and
   a new BGP Capability allowing MP-BGP Peers to dynamically discover
   whether they can exchange IPv4 NLRI and VPN-IPv4 NLRI with an IPv6
   Next Hop.

   With this new MP-BGP capability exchange allows the BGP peering
   session to act as a pure transport to allow the session to carry
   Address Family Identifier (AFI) and the Subsequent Address Family
   Identifier (SAFI) for both IPv4 and IPv6.

   Furthermore, a number of these existing AFI/SAFIs allow the Next Hop
   to belong to either the IPv4 Network Layer Protocol or the IPv6
   Network Layer Protocol, and specify the encoding of the Next Hop
   information to determine which of the protocols the address actually

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   belongs to.  For example, [RFC4684] allows the Next Hop address to be
   either IPv4 or IPv6 and states that the Next Hop field address shall
   be interpreted as an IPv4 address whenever the length of Next Hop
   address is 4 octets, and as an IPv6 address whenever the length of
   the Next Hop address is 16 octets.

   For example, the AFI/SAFI <25/65> used (as per [RFC6074]) to perform
   L2VPN auto-discovery, allows advertising NLRI that contains the
   identifier of a Virtual Private LAN Service (VPLS) instance or that
   identifies a particular pool of attachment circuits at a given
   Provider Edge (PE), while the Next Hop field contains the loopback
   address of a PE.  Similarly, the AFI/SAFI <1/132> (defined in
   [RFC4684]) to advertise Route Target (RT) membership information,
   allows advertising NLRI that contains such RT membership information,
   while the Next Hop field contains the address of the advertising
   router.

   There are situations such as those described in [RFC4925] and in
   [RFC5565] where carriers (or large enterprise networks acting as
   carrier for their internal resources) may be required to establish
   connectivity between 'islands' of networks of one address family type
   across a transit core of a differing address family type.  This
   includes both the case of IPv6 islands across an IPv4 core and the
   case of IPv4 islands across an IPv6 core.  Where Multiprotocol BGP
   (MP-BGP) is used to advertise the corresponding reachability
   information, this translates into the requirement for a BGP speaker
   to advertise Network Layer Reachability Information (NLRI) of a given
   address family via a Next Hop of a different address family (i.e.,
   IPv6 NLRI with IPv4 Next Hop and IPv4 NLRI with IPv6 Next Hop).

   The current AFI/SAFI definitions for the IPv6 address family assume
   that the Next Hop address belongs to the IPv6 address family type.
   Specifically, as per [RFC2545] and [RFC8277], when the <AFI/SAFI> is
   <2/1>, <2/2>, or <2/4>, the Next Hop address is assumed to be of IPv6
   type.  As per [RFC4659], when the <AFI/SAFI> is <2/128>, the Next Hop
   address is assumed to be of IPv6-VPN type.

   However, [RFC4798] and [RFC4659] specify how an IPv4 address can be
   encoded inside the Next Hop IPv6 address field when IPv6 NLRI needs
   to be advertised with an IPv4 Next Hop.  [RFC4798] defines how the
   IPv4-mapped IPv6 address format specified in the IPv6 addressing
   architecture ([RFC4291]) can be used for that purpose when the <AFI/
   SAFI> is <2/1>, <2/2>, or <2/4>.  [RFC4659] defines how the IPv4-
   mapped IPv6 address format as well as a null Route Distinguisher can
   be used for that purpose when the <AFI/SAFI> is <2/128>.  Thus, there
   are existing solutions for the advertisement of IPv6 NLRI with an
   IPv4 Next Hop.

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   Similarly, the current AFI/SAFI definitions for advertisement of IPv4
   NLRI or VPN-IPv4 NLRI assume that the Next Hop address belongs to the
   IPv4 address family type.  Specifically, as per [RFC4760] and
   [RFC8277], when the <AFI/SAFI> is <1/1>, <1/2>, or <1/4>, the Next
   Hop address is assumed to be of IPv4 type.  As per [RFC4364], when
   the <AFI/SAFI> is <1/128>, the Next Hop address is assumed to be of
   VPN-IPv4 type.  As per [RFC6513] and [RFC6514], when the <AFI/SAFI>
   is <1/129>, the Next Hop address is assumed to be of VPN-IPv4 type.
   There is clearly no generally applicable method for encoding an IPv6
   address inside the IPv4 address field of the Next Hop.  Hence, there
   is currently no specified solution for advertising IPv4 or VPN-IPv4
   NLRI with an IPv6 Next Hop.

   A new specification for carrying IPv4 Network Layer Reachability
   Information (NLRI) of a given address family via a Next Hop of a
   different address family is now defined in [RFC5549], and specifies
   the extensions necessary to do so.  This comprises an extension of
   the AFI/SAFI definitions to allow the address of the Next Hop for
   IPv4 NLRI or VPN-IPv4 NLRI to belong to either the IPv4 or the IPv6
   protocol, the encoding of the Next Hop information to determine which
   of the protocols the address actually belongs to, and a new BGP
   Capability allowing MP-BGP peers to dynamically discover whether they
   can exchange IPv4 NLRI and VPN- IPv4 NLRI with an IPv6 Next Hop.

   With the new extensions defined in [RFC5549] supporting Network Layer
   Reachability Information (NLRI) and next hop address family mismatch,
   the BGP peer session can now be treated as a pure transport and carry
   both IPv4 and IPv6 NLRI at the PE-CE edge over a single IPv6 TCP
   session.  This allows for the elimination of dual stack from the PE-
   CE peering point, and now allow the peering to be IPv6-ONLY.  The
   elimination of IPv4 on the PE-CE peering points translates into OPEX
   expenditure savings of point-to-point infrastructure links as well as
   /31 address space savings and administration and network management
   of both IPv4 and IPv6 BGP peers.  This reduction decreases the number
   of PE-CE BGP peers by fifty percent, which is a tremendous cost
   savings for all Enterprises and Service Providers.

   While the savings exists at the PE-CE edge, on the core side PE to
   Route Reflector peering carrying <AFI/SAFI> IPv4 <1/1>, VPN-IPV4
   <1/128>, and Multicasat VPN <1/129>, the cost savings nets to a break
   even to be the same as with an IPV4 Core carrying IPv6 NLRI IPV6
   <2/1>, VPN-IPV6 <2/128>, and Multicasat VPN <2/129>.  This document
   also provides a possible solution for IXPs (Internet Exchange points)
   that are facing IPv4 address depletion at these peering points to use
   BGP-MP capability exchange defined in [RFC5549] to carry IPv4
   (Network Layer Reachability Information) NLRI in an IPv6 next hop
   using the [RFC5565] softwire mesh framework.

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2.  Requirements Language

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

3.  eBGP PE-CE IPv4 and IPv6 NLRI over IPv6 Next Hop Peer Use Case
    Interop Testing

   This particualr use case for external BGP PE-CE edge peering
   interoperability testing defined in this draft utilizing [RFC8950]
   next hop encoding to carry both IPv4 and IPv6 NLRI over an IPv6 Next
   hop encoded peer.  Today the IPv4 NLRI and IPv6 NLRI are carried over
   separate BGP sessions based on the address family of the NLRI being
   transported.  With this drafts use case, the IPv6 NLRI Unicast SAFI
   along with now the IPv4 NLRI Unicast SAFI, is now being carried by
   the sinlge transport style IPv6 next hop peer.

   This document describes the use case of advertising with IPv4 NLRI
   over IPv6 Next hop with MP_REACH_NLRI with:

   o  AFI = 1

   o  SAFI = 1

   o  Length of Next Hop Address = 16 or 32

   o  Next Hop Address = IPv6 address of next hop (potentially followed
      by the link-local IPv6 address of the next hop).  This field is to
      be constructed as per Section 3 of [RFC2545].

   The BGP speaker receiving the advertisement MUST use the Length of
   Next Hop Address field to determine which network-layer protocol the
   next hop address belongs to.

   Note that this method of using the Length of the Next Hop Address
   field to determine which network-layer protocol the next hop address
   belongs to (out of the set of protocols allowed by the AFI/SAFI
   definition) is the same as used in [RFC4684] and [RFC6074].

4.  RFC 8950 updates to RFC 5549

   This section describes the updates to [RFC8950] next hop encoding
   from [RFC5549].  In [RFC5549] when AFI/SAFI 1/128 is used, the next-
   hop address is encoded as an IPv6 address with a length of 16 or 32
   bytes.  To accommodate all existing implementations and bring

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   consistency with VPNv4oIPv4 and VPNv6oIPv6, this document modifies
   how the next-hop address is encoded.  The next-hop address is now
   encoded as a VPN-IPv6 address with a length of 24 or 48 bytes
   [RFC8950] (see Sections 3 and 6.2).  This change addresses Erratum ID
   5253 (Err5253).  As all known and deployed implementations are
   interoperable today and use the new proposed encoding, the change
   does not break existing interoperability.

   [RFC5549] next hop encoding of MP_REACH_NLRI with:

   o  AFI = 1

   o  SAFI = 1, 2, or 4

   o  Length of Next Hop Address = 16 or 32

   o  Next Hop Address = IPv6 address of next hop (potentially followed
      by the link-local IPv6 address of the next hop).  This field is to
      be constructed as per Section 3 of [RFC2545].

   o  NLRI= NLRI as per current AFI/SAFI definition

   It also allows advertising with [RFC4760] of an MP_REACH_NLRI with:

   o  AFI = 1

   o  SAFI = 128 or 129

   o  Length of Next Hop Address = 16 or 32

   o  NLRI= NLRI as per current AFI/SAFI definition

   [RFC8950] next hop encoding of MP_REACH_NLRI with:

   o  AFI = 1

   o  SAFI = 1, 2, or 4

   o  Length of Next Hop Address = 16 or 32

   o  Next Hop Address = IPv6 address of next hop (potentially followed
      by the link-local IPv6 address of the next hop).  This field is to
      be constructed as per Section 3 of [RFC2545].

   o  NLRI= NLRI as per current AFI/SAFI definition

   It also allows advertising with [RFC4760] of an MP_REACH_NLRI with:

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   o  AFI = 1

   o  SAFI = 128 or 129

   o  Length of Next Hop Address = 24 or 48

   o  Next Hop Address = VPN-IPv6 address of next hop with an 8-octet RD
      set to zero (potentially followed by the link-local VPN-IPv6
      address of the next hop with an 8-octet RD is set to zero).

   o  NLRI= NLRI as per current AFI/SAFI definition

5.  Operational Improvements with Single IPv6 transport peer

   As Enterprises and Service Providers migrate their IPv4 core to an
   MPLS LDPv6 or SRv6 transport, they must continue to be able to
   support legacy IPv4 customers.  With the new extensions defined in
   [RFC4760], supporting Network Layer Reachability Information (NLRI)
   and next hop address family mismatch, the BGP peer session can now be
   treated as a pure transport and carry both IPv4 and IPv6 NLRI at the
   PE-CE edge.  This paves the way to now eliminate dual stacking on all
   PE-CE peering points to customers making the peering IPv6 only.  With
   this change all IPv4 and IPv6 Network Layer Reachability Information
   (NLRI) will now be carried over a single BGP session.  This also
   solves the dual stack issue with IXP (Internet Exchange Points)
   having to maintain separate peering for both IPv4 and IPv6.  From an
   operations perspective the PE-CE edge peering will be drastically
   simplified with the elimination of IPv4 peers yielding a reduction of
   peers by 50 percent.  From an operations perspective prior to
   elimination of IPv4 peers an audit is recommended to identify and
   IPv4 and IPv6 peering incongruencies that may exist and to rectify
   prior to elimination of the IPv4 peers.  No operational impacts or
   issues are expected with this change.

6.  Operational Considerations

   With a sinlge IPv6 Peer carrying both IPv4 and IPv6 NLRI there are
   some operational considerations in terms of what changes and what
   does not change.

   What does not change with a single IPv6 transport peer carrying IPv4
   NLRI and IPv6 NLRI below:

   Routing Policy configuration is still separate for IPv4 and IPv6
   configured by capability as previously

   Layer 1, Layer 2 issues such as 1 way fiber or fiber cut will impact
   both IPv4 and IPv6 as previously.

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   If the interface is admin down the IPv6 peer would go down and IPv4
   NLRI and IPv6 NLRI would be withdrawn as previously.

   What does change with a single IPv6 transport peer carrying IPv4 NLRI
   and IPv6 NLRI below:

   Physical interface is no longer dual stacked.  Any change in IPv6
   address or DAD state will impact both IPv4 and IPv6 NLRI exchange

   Single BFD session for both IPv4 and IPv6 NLRI fate sharing as the
   session is now tied to the transport which now is only IPv6 address
   family

   Both IPv4 and IPv6 peer now exists under the IPv4 address family
   configuration

   Fate sharing of IPv4 and IPv6 address family from a logical
   perspective now carried over a single IPv6 peer

7.  IANA Considerations

   There are not any IANA considerations.

8.  Security Considerations

   The extensions defined in this document allow BGP to propagate
   reachability information about IPv6 routes over an MPLS IPv4 core
   network.  As such, no new security issues are raised beyond those
   that already exist in BGP-4 and use of MP-BGP for IPv6.  The security
   features of BGP and corresponding security policy defined in the ISP
   domain are applicable.  For the inter-AS distribution of IPv6 routes
   according to case (a) of Section 4 of this document, no new security
   issues are raised beyond those that already exist in the use of eBGP
   for IPv6 [RFC2545].

9.  Acknowledgments

10.  References

10.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

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   [RFC2545]  Marques, P. and F. Dupont, "Use of BGP-4 Multiprotocol
              Extensions for IPv6 Inter-Domain Routing", RFC 2545,
              DOI 10.17487/RFC2545, March 1999,
              <https://www.rfc-editor.org/info/rfc2545>.

   [RFC4291]  Hinden, R. and S. Deering, "IP Version 6 Addressing
              Architecture", RFC 4291, DOI 10.17487/RFC4291, February
              2006, <https://www.rfc-editor.org/info/rfc4291>.

   [RFC4364]  Rosen, E. and Y. Rekhter, "BGP/MPLS IP Virtual Private
              Networks (VPNs)", RFC 4364, DOI 10.17487/RFC4364, February
              2006, <https://www.rfc-editor.org/info/rfc4364>.

   [RFC4760]  Bates, T., Chandra, R., Katz, D., and Y. Rekhter,
              "Multiprotocol Extensions for BGP-4", RFC 4760,
              DOI 10.17487/RFC4760, January 2007,
              <https://www.rfc-editor.org/info/rfc4760>.

   [RFC5492]  Scudder, J. and R. Chandra, "Capabilities Advertisement
              with BGP-4", RFC 5492, DOI 10.17487/RFC5492, February
              2009, <https://www.rfc-editor.org/info/rfc5492>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

   [RFC8277]  Rosen, E., "Using BGP to Bind MPLS Labels to Address
              Prefixes", RFC 8277, DOI 10.17487/RFC8277, October 2017,
              <https://www.rfc-editor.org/info/rfc8277>.

10.2.  Informative References

   [I-D.ietf-idr-dynamic-cap]
              Ramachandra, S. and E. Chen, "Dynamic Capability for BGP-
              4", draft-ietf-idr-dynamic-cap-14 (work in progress),
              December 2011.

   [RFC4659]  De Clercq, J., Ooms, D., Carugi, M., and F. Le Faucheur,
              "BGP-MPLS IP Virtual Private Network (VPN) Extension for
              IPv6 VPN", RFC 4659, DOI 10.17487/RFC4659, September 2006,
              <https://www.rfc-editor.org/info/rfc4659>.

   [RFC4684]  Marques, P., Bonica, R., Fang, L., Martini, L., Raszuk,
              R., Patel, K., and J. Guichard, "Constrained Route
              Distribution for Border Gateway Protocol/MultiProtocol
              Label Switching (BGP/MPLS) Internet Protocol (IP) Virtual
              Private Networks (VPNs)", RFC 4684, DOI 10.17487/RFC4684,
              November 2006, <https://www.rfc-editor.org/info/rfc4684>.

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   [RFC4798]  De Clercq, J., Ooms, D., Prevost, S., and F. Le Faucheur,
              "Connecting IPv6 Islands over IPv4 MPLS Using IPv6
              Provider Edge Routers (6PE)", RFC 4798,
              DOI 10.17487/RFC4798, February 2007,
              <https://www.rfc-editor.org/info/rfc4798>.

   [RFC4925]  Li, X., Ed., Dawkins, S., Ed., Ward, D., Ed., and A.
              Durand, Ed., "Softwire Problem Statement", RFC 4925,
              DOI 10.17487/RFC4925, July 2007,
              <https://www.rfc-editor.org/info/rfc4925>.

   [RFC5549]  Le Faucheur, F. and E. Rosen, "Advertising IPv4 Network
              Layer Reachability Information with an IPv6 Next Hop",
              RFC 5549, DOI 10.17487/RFC5549, May 2009,
              <https://www.rfc-editor.org/info/rfc5549>.

   [RFC5565]  Wu, J., Cui, Y., Metz, C., and E. Rosen, "Softwire Mesh
              Framework", RFC 5565, DOI 10.17487/RFC5565, June 2009,
              <https://www.rfc-editor.org/info/rfc5565>.

   [RFC6074]  Rosen, E., Davie, B., Radoaca, V., and W. Luo,
              "Provisioning, Auto-Discovery, and Signaling in Layer 2
              Virtual Private Networks (L2VPNs)", RFC 6074,
              DOI 10.17487/RFC6074, January 2011,
              <https://www.rfc-editor.org/info/rfc6074>.

   [RFC6513]  Rosen, E., Ed. and R. Aggarwal, Ed., "Multicast in MPLS/
              BGP IP VPNs", RFC 6513, DOI 10.17487/RFC6513, February
              2012, <https://www.rfc-editor.org/info/rfc6513>.

   [RFC6514]  Aggarwal, R., Rosen, E., Morin, T., and Y. Rekhter, "BGP
              Encodings and Procedures for Multicast in MPLS/BGP IP
              VPNs", RFC 6514, DOI 10.17487/RFC6514, February 2012,
              <https://www.rfc-editor.org/info/rfc6514>.

   [RFC8126]  Cotton, M., Leiba, B., and T. Narten, "Guidelines for
              Writing an IANA Considerations Section in RFCs", BCP 26,
              RFC 8126, DOI 10.17487/RFC8126, June 2017,
              <https://www.rfc-editor.org/info/rfc8126>.

   [RFC8950]  Litkowski, S., Agrawal, S., Ananthamurthy, K., and K.
              Patel, "Advertising IPv4 Network Layer Reachability
              Information (NLRI) with an IPv6 Next Hop", RFC 8950,
              DOI 10.17487/RFC8950, November 2020,
              <https://www.rfc-editor.org/info/rfc8950>.

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Appendix A.  IPv4 NLRI IPv6 Next Hop Vendor Testing

   IPv4 NLRI with IPv6 Next Hop encoding is supported for all BGP peers
   both iBGP and eBGP.

   This section details the vendor support QA testing of RFC 8950 Next
   Hop Encoding for "PE-CE eBGP" using GUA (Global Unicast Address),
   Link Local (LL) peering.  This drafts goal is to first ensure that QA
   testing of all features and functionality works with "eBGP PE-CE" use
   case single peer carrying both IPv4 NLRI and IPv6 NLRI and that the
   routing policy features are all still fully functionality do not
   change.

A.1.  Router and Switch Vendors Support and Quality Assurance
      Engineering Lab Results.

        +-----------+----------------+---------------+-----------+
        | Vendor    | PE-CE eBGP GUI | PE-CE eBGP LL | QA Tested |
        +-----------+----------------+---------------+-----------+
        | Cisco     |      ***       |               |           |
        | Juniper   |      ***       |               |           |
        | Nokia/ALU |      ***       |               |           |
        | Arista    |      ***       |               |           |
        | Huawei    |      ***       |               |           |
        +-----------+----------------+---------------+-----------+

                          Table 1: Vendor Support

A.2.  Router and Switch Vendors Interoperability Lab Results.

   This section details the vendor interoperability testing and support
   of RFC5549 that all features and functionality works with "eBGP PE-
   CE" use case with having a single peer carrying both IPv4 NLRI and
   IPv6 NLRI and that the routing policy features are fully tested for
   quality assurance.

       +-----------+-------+---------+-----------+--------+--------+
       | Vendor    | Cisco | Juniper | Nokia/ALU | Arista | Huawei |
       +-----------+-------+---------+-----------+--------+--------+
       | Cisco     |  N/A  |         |           |        |        |
       | Juniper   |       |   N/A   |           |        |        |
       | Nokia/ALU |       |         |    N/A    |        |        |
       | Arista    |       |         |           |  N/A   |        |
       | Huawei    |       |         |           |        |  N/A   |
       +-----------+-------+---------+-----------+--------+--------+

                          Table 2: Vendor Interop

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Authors' Addresses

   Gyan Mishra
   Verizon Inc.

   Email: gyan.s.mishra@verizon.com

   Mankamana Mishra
   Cisco Systems
   821 Alder Drive,
   MILPITAS  CALIFORNIA 95035

   Email: mankamis@cisco.com

   Jeff Tantsura
   Apstra, Inc.

   Email: jefftant.ietf@gmail.com

   Lili Wang
   Juniper Networks, Inc.
   10 Technology Park Drive,
   Westford  MA 01886
   US

   Email: liliw@juniper.net

   Qing Yang
   Arista Networks

   Email: qyang@arista.com

   Adam Simpson
   Nokia

   Email: adam.1.simpson@nokia.com

   Shuanglong Chen
   Huawei Technologies

   Email: chenshuanglong@huawei.com

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