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6man                                                           R. Bonica
Internet-Draft                                          Juniper Networks
Intended status: Standards Track                               Y. Kamite
Expires: March 5, 2020                    NTT Communications Corporation
                                                                 T. Niwa
                                                                    KDDI
                                                               A. Alston
                                                            D. Henriques
                                                          Liquid Telecom
                                                                   N. So
                                                                   F. Xu
                                                            Reliance Jio
                                                                 G. Chen
                                                                   Baidu
                                                                  Y. Zhu
                                                                 G. Yang
                                                           China Telecom
                                                                 Y. Zhou
                                                               ByteDance
                                                       September 2, 2019


                The IPv6 Compressed Routing Header (CRH)
                   draft-bonica-6man-comp-rtg-hdr-07

Abstract

   This document defines two new IPv6 Routing header types.
   Generically, they are called the Compressed Routing Header (CRH).
   More specifically, the 16-bit version of the CRH is called the CRH-
   16, while the 32-bit version of the CRH is called the CRH-32.  SRv6+
   nodes use the CRH to steer packets from segment to segment along
   SRv6+ paths.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

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



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   This Internet-Draft will expire on March 5, 2020.

Copyright Notice

   Copyright (c) 2019 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 . . . . . . . . . . . . . . . . . . . .   3
   3.  The Compressed Routing Header (CRH) . . . . . . . . . . . . .   3
   4.  The Segment Forwarding Information Base (SFIB)  . . . . . . .   4
   5.  Processing Rules  . . . . . . . . . . . . . . . . . . . . . .   5
     5.1.  General . . . . . . . . . . . . . . . . . . . . . . . . .   5
     5.2.  CRH Specific  . . . . . . . . . . . . . . . . . . . . . .   6
       5.2.1.  Computing Minimum CRH Length  . . . . . . . . . . . .   7
       5.2.2.  Topological Instructions That Control Adjacency
               Segments  . . . . . . . . . . . . . . . . . . . . . .   8
       5.2.3.  Topological Instructions That Control Node Segments .   8
   6.  Mutability  . . . . . . . . . . . . . . . . . . . . . . . . .   9
   7.  Compliance  . . . . . . . . . . . . . . . . . . . . . . . . .   9
   8.  Management Considerations . . . . . . . . . . . . . . . . . .   9
   9.  Security Considerations . . . . . . . . . . . . . . . . . . .   9
   10. IANA Considerations . . . . . . . . . . . . . . . . . . . . .   9
   11. Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  10
   12. References  . . . . . . . . . . . . . . . . . . . . . . . . .  10
     12.1.  Normative References . . . . . . . . . . . . . . . . . .  10
     12.2.  Informative References . . . . . . . . . . . . . . . . .  10
   Appendix A.  CRH Processing Examples  . . . . . . . . . . . . . .  11
     A.1.  SR Path Contains Node Segments Only . . . . . . . . . . .  12
     A.2.  SR Path Contains Node Segments Only And Preserves The
           First SID . . . . . . . . . . . . . . . . . . . . . . . .  13
     A.3.  SR Path Contains Adjacency Segments Only  . . . . . . . .  13
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  14






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1.  Introduction

   This document defines two new IPv6 [RFC8200] Routing header types.
   Generically, they are called the Compressed Routing Header (CRH).
   More specifically, the 16-bit version of the CRH is called the CRH-
   16, while the 32-bit version of the CRH is called the CRH-32.  SRv6+
   [I-D.bonica-spring-srv6-plus] nodes use the CRH to steer packets from
   segment to segment along SRv6+ paths.

   For details regarding SRv6+ paths, segments, Segment Identifiers
   (SIDs) and instructions, see [I-D.bonica-spring-srv6-plus].

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.  The Compressed Routing Header (CRH)

   Both CRH versions (i.e., CRH-16 and CRH-32) contain the following
   fields:

   o  Next Header - Defined in [RFC8200].  Identifies the type of header
      immediately following the CRH.

   o  Hdr Ext Len - Defined in [RFC8200].  Length of the CRH in 8-octet
      units, not including the first 8 octets.

   o  Routing Type - Defined in [RFC8200].  Value TBD by IANA.  (For
      CRH-16, the suggested value is 5.  For CRH-32, the suggested value
      is 6.)

   o  Segments Left - Defined in [RFC8200].  Number of route segments
      remaining, i.e., number of explicitly listed intermediate nodes
      still to be visited before reaching the final destination.

   o  SID List - Represents the SRv6+ path as an ordered list of SIDs.
      SIDs are listed in reverse order, with SID[0] representing the
      final segment, SID[1] representing the penultimate segment, and so
      forth.  SIDs are listed in reverse order so that Segments Left can
      be used as an index to the SID List.  The SID indexed by Segments
      Left is called the current SID.

   In the CRH-16 (Figure 1), each SID list entry is encoded in 16-bits.
   In the CRH-32 (Figure 2), each SID list entry is encoded in 32-bits.



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   In networks where the smallest feasible Maximum SID Value (MSV)
   [I-D.bonica-spring-srv6-plus] is greater than 65,635, CRH-32 is
   required.  Otherwise, CRH-16 is preferred.

   In all cases, the CRH MUST end on a 64-bit boundary.  Therefore, the
   CRH MAY be padded with zeros.

        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
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |  Next Header  |  Hdr Ext Len  | Routing Type  | Segments Left |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |             SID[0]            |          SID[1]               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-|
       |                          .........
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-



                             Figure 1: CRH-16

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  Next Header  |  Hdr Ext Len  | Routing Type  | Segments Left |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      +                             SID[0]                            +
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      +                             SID[1]                            +
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      //                                                              //
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      +                             SID[n]                            +
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


                             Figure 2: CRH-32

4.  The Segment Forwarding Information Base (SFIB)

   A segment ingress node MUST maintain one Segment Forwarding
   Information Base (SFIB) entry for each segment that it originates.
   Each SFIB entry contains the following information:

   o  A SID.

   o  A segment type.




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   o  Topological instruction parameters.

   The following are valid segment types:

   o  Adjacency.

   o  Node.

   The following parameters are associated with topological instructions
   that control adjacency segments:

   o  An IPv6 address that identifies an interface on the segment egress
      node.

   o  An interface identifier.

   Node segments are associated with a single topological instruction
   parameter.  This parameter is an IPv6 address that identifies an
   interface on the segment egress node.

5.  Processing Rules

5.1.  General

   [RFC8200] defines rules that apply to IPv6 extension headers, in
   general, and IPv6 Routing headers, in particular.  All of these rules
   apply to the CRH.

   For example:

   o  Extension headers (except for the Hop-by-Hop Options header) are
      not processed, inserted, or deleted by any node along a packet's
      delivery path, until the packet reaches the node (or each of the
      set of nodes, in the case of multicast) identified in the
      Destination Address field of the IPv6 header.

   o  If, while processing a received packet, a node encounters a
      Routing header with an unrecognized Routing Type value, the
      required behavior of the node depends on the value of the Segments
      Left field.  If Segments Left is zero, the node must ignore the
      Routing header and proceed to process the next header in the
      packet, whose type is identified by the Next Header field in the
      Routing header.  If Segments Left is non-zero, the node must
      discard the packet and send an ICMPv6 [RFC4443] Parameter Problem,
      Code 0, message to the packet's Source Address, pointing to the
      unrecognized Routing Type.





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   o  If, after processing a Routing header of a received packet, an
      intermediate node determines that the packet is to be forwarded
      onto a link whose link MTU is less than the size of the packet,
      the node must discard the packet and send an ICMPv6 Packet Too Big
      message to the packet's Source Address.

5.2.  CRH Specific

   When a node recognizes and processes a CRH, it executes the following
   procedure:

   o  If the IPv6 Source Address is a link-local address, discard the
      packet.

   o  If the IPv6 Source Address is a multicast address, discard the
      packet.

   o  If Segments Left equals 0, skip over the CRH and process the next
      header in the packet.

   o  If Hdr Ext Len indicates that the CRH is larger than the
      implementation can process, discard the packet and send an ICMPv6
      Parameter Problem, Code 0, message to the Source Address, pointing
      to the Hdr Ext Len field.

   o  Compute L, the minimum CRH length (See Section 5.2.1).

   o  If L is greater than Hdr Ext Len, discard the packet and send an
      ICMPv6 Parameter Problem, Code 0, message to the Source Address,
      pointing to the Segments Left field.

   o  Decrement the packet's Hop Count.

   o  If the Hop Count has expired, discard the packet and send an
      ICMPv6 Time Expired message to the packet's source node.

   o  Decrement Segments Left

   o  Search for the current SID in the SFIB.

   o  If the above-mentioned search does not return an SFIB entry,
      discard the packet and send an ICMPv6 Parameter Problem, Code 0,
      message to the Source Address, pointing to the current SID.

   o  If the above-mentioned search returns an SFIB entry that
      represents an adjacency segment, execute the topological
      instruction described in Section 5.2.2.




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   o  If the above-mentioned search returns an SFIB entry that
      represents a node segment, execute the topological instruction
      described in Section 5.2.3.

   The above stated rules are demonstrated in Appendix A.

5.2.1.  Computing Minimum CRH Length

   The algorithm described in this section accepts the following CRH
   fields as its input parameters:

   o  Routing Type (i.e., CRH-16 or CRH-32).

   o  Segments Left.

   It yields L, the minimum CRH length.  The minimum CRH length is
   measured in 8-octet units, not including the first 8 octets.

             <CODE BEGINS>

             switch(Routing Type) {
                 case CRH-16:
                     sidsBeyondFirstWord = Segments Left - 2;
                     sidPerWord = 4;
                 case CRH-32:
                     sidsBeyondFirstWord = Segments Left - 1;
                     sdsPerWord = 2;
                 case default:
                     return(0xFF);
                 }

             if (sidsBeyondFirstWord <= 0)
                 return(0)

             words = sidsBeyondFirstWord div sidsPerWord;
             if (sidsBeyondFirstWord mod sidsPerWord)
                 words++;

             return(words)


             <CODE ENDS>









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5.2.2.  Topological Instructions That Control Adjacency Segments

   A topological instruction that controls an adjacency segment accepts
   the following parameters:

   o  An IPv6 address that identifies an interface on the segment egress
      node.

   o  An interface identifier.

   The instruction behaves as follows:

   o  If the interface that was received as a parameter is not
      operational, discard the packet and send an ICMPv6 Destination
      Unreachable message (Code: 5, Source Route Failed) to the packet's
      source node.

   o  Overwrite the packet's Destination Address with the IPv6 address
      that was received as a parameter.

   o  Forward the packet through the above-mentioned interface.

5.2.3.  Topological Instructions That Control Node Segments

   A topological instruction that controls a node segment accepts a
   single parameter.  This parameter is an IPv6 address that identifies
   an interface on the segment egress node.

   The instruction behaves as follows:

   o  If the segment ingress node does not have a viable route to the
      IPv6 address included as a parameter, discard the packet and send
      an ICMPv6 Destination Unreachable message (Code:1 Net Unreachable)
      to the packet's source node.

   o  Overwrite the packet's Destination Address with the destination
      address that was included as a parameter.

   o  Forward the packet to the next hop along the least cost path to
      the segment egress node.  If there are multiple least cost paths
      to the segment egress node (i.e., Equal Cost Multipath), execute
      procedures so that all packets belonging to a flow are forwarded
      through the same next hop.








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6.  Mutability

   In the CRH, the Segments Left field is mutable.  All remaining fields
   are immutable.

7.  Compliance

   In order to be compliant with this specification, an SRv6+
   implementation MUST:

   o  Be able to process IPv6 options as described in Section 4.2 of
      [RFC8200].

   o  Be able to process the Routing header as described in Section 4.4
      of [RFC8200].

   o  Support the CRH-16 and the CRH-32.

8.  Management Considerations

   PING and TRACEROUTE [RFC2151] both operate correctly in the presence
   of the CRH.

9.  Security Considerations

   SRv6+ domains MUST NOT span security domains.  In order to enforce
   this requirement, security domain edge routers MUST do one of the
   following:

   o  Discard all inbound SRv6+ packets whose IPv6 destination address
      represents domain infrastructure.

   o  Authenticate [RFC4302] [RFC4303] all inbound SRv6+ packets whose
      IPv6 destination address represents domain infrastructure.

10.  IANA Considerations

   IANA is requested to make the following entries in the Internet
   Protocol Version 6 (IPv6) Parameters "Routing Type" registry:

     Suggested
     Value            Description                           Reference
   -----------------------------------------------------------------------
       5      Compressed Routing Header (16-bit) (CRH-16)   This document
       6      Compressed Routing Header (32-bit) (CRH-32)   This document






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11.  Acknowledgements

   Thanks to Naveen Kottapalli, Joel Halpern, Tony Li, Gerald Schmidt,
   Nancy Shaw, and Chandra Venkatraman for their comments.

12.  References

12.1.  Normative References

   [I-D.bonica-spring-srv6-plus]
              Bonica, R., Hegde, S., Kamite, Y., Alston, A., Henriques,
              D., Halpern, J., Linkova, J., and G. Chen, "IPv6 Support
              for Segment Routing: SRv6+", draft-bonica-spring-
              srv6-plus-04 (work in progress), July 2019.

   [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>.

   [RFC4302]  Kent, S., "IP Authentication Header", RFC 4302,
              DOI 10.17487/RFC4302, December 2005,
              <https://www.rfc-editor.org/info/rfc4302>.

   [RFC4303]  Kent, S., "IP Encapsulating Security Payload (ESP)",
              RFC 4303, DOI 10.17487/RFC4303, December 2005,
              <https://www.rfc-editor.org/info/rfc4303>.

   [RFC4443]  Conta, A., Deering, S., and M. Gupta, Ed., "Internet
              Control Message Protocol (ICMPv6) for the Internet
              Protocol Version 6 (IPv6) Specification", STD 89,
              RFC 4443, DOI 10.17487/RFC4443, March 2006,
              <https://www.rfc-editor.org/info/rfc4443>.

   [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>.

   [RFC8200]  Deering, S. and R. Hinden, "Internet Protocol, Version 6
              (IPv6) Specification", STD 86, RFC 8200,
              DOI 10.17487/RFC8200, July 2017,
              <https://www.rfc-editor.org/info/rfc8200>.

12.2.  Informative References







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   [RFC2151]  Kessler, G. and S. Shepard, "A Primer On Internet and TCP/
              IP Tools and Utilities", FYI 30, RFC 2151,
              DOI 10.17487/RFC2151, June 1997,
              <https://www.rfc-editor.org/info/rfc2151>.

Appendix A.  CRH Processing Examples

   This appendix demonstrates CRH processing in the following scenarios:

   o  SR path contains node segments only (Appendix A.1).

   o  SR path contains node segments only and preserves the first SID
      (Appendix A.2).

   o  SR path contains adjacency segments only (Appendix A.3).

                                -----------
            2001:db8:0:2/64    |Node: I2   |   2001:db8:0:4/64
         ----------------------|Loopback:  |--------------------
        |                  ::2 |2001:db8::2| ::1                |
        |                       -----------                     |
        | ::1                                               :: 2|
    -----------                 -----------                 -----------
   |Node: S    |2001:db8:0:1/64|Node: I1   |2001:db8:0:3/64|Node: I3   |
   |Loopback   |---------------|Loopback:  |---------------|Loopback:  |
   |2001:db8::a| ::1       ::2 |2001:db8::1| ::1       ::2 |2001:db8::3|
    -----------                 -----------                 -----------
                                                                 | ::1
                                -----------                      |
                               |Node: D    |   2001:db8:0:b/64   |
                               |Loopback:  |---------------------
                               |2001:db8::b| ::2
                                -----------

                       Figure 3: Reference Topology

   Figure 3 provides a reference topology that is used in all examples.














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        +--------------------+-----+--------------+--------------+
        | Instantiating Node | SID | Segment Type | IPv6 Address |
        +--------------------+-----+--------------+--------------+
        |        All         | 1   | Node         | 2001:db8::1  |
        |        All         | 2   | Node         | 2001:db8::2  |
        |        All         | 3   | Node         | 2001:db8::3  |
        |        All         | 10  | Node         | 2001:db8::a  |
        |        All         | 11  | Node         | 2001:db8::b  |
        +--------------------+-----+--------------+--------------+

                            Table 1: Node SIDs

   Table 1 describes SFIB entries that are instantiated on all nodes.
   All of these SFIB entries represent node segments.

        +--------------------+-----+-----------------+-----------+
        | Instantiating Node | SID |   IPv6 Address  | Interface |
        +--------------------+-----+-----------------+-----------+
        |         S          | 129 | 2001:db8:0:1::2 |  S -> I1  |
        |         S          | 130 | 2001:db8:0:2::2 |  S -> I2  |
        |         I1         | 129 | 2001:db8:0:3::2 |  I1 -> I3 |
        |         I2         | 129 | 2001:db8:0:4::2 |  I2 -> I3 |
        |         I3         | 129 | 2001:db8:0:b::2 |  I3 -> D  |
        +--------------------+-----+-----------------+-----------+

                          Table 2: Adjacency SIDs

   Table 2 describes SFIB entries that are instantiated on specific
   nodes.  All of these SFIB entries represent adjacency segments.

A.1.  SR Path Contains Node Segments Only

   In this example, Node S sends a packet to Node D, though a node
   segment that terminates on I3.  In this example, I3 does not appear
   in the CRH segment list.  Therefore, the destination node may not be
   able to send return traffic through the same path.

        +-------------------------------------+-------------------+
        | As the packet travels from S to I3: |                   |
        +-------------------------------------+-------------------+
        | Source Address = 2001:db8::a        | Segments Left = 1 |
        | Destination Address = 2001:db8::3   | SID[0] = 11       |
        +-------------------------------------+-------------------+








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        +-------------------------------------+-------------------+
        | As the packet travels from I3 to D: |                   |
        +-------------------------------------+-------------------+
        | Source Address = 2001:db8::a        | Segments Left = 0 |
        | Destination Address = 2001:db8::b   | SID[0] = 11       |
        +-------------------------------------+-------------------+

A.2.  SR Path Contains Node Segments Only And Preserves The First SID

   In this example, Node S sends a packet to Node D, through a node
   segment that terminates on I3.  In this example, I3 appears in the
   CRH segment list.  Therefore, the destination node can send return
   traffic through the same path.

        +-------------------------------------+-------------------+
        | As the packet travels from S to I3: |                   |
        +-------------------------------------+-------------------+
        | Source Address = 2001:db8::a        | Segments Left = 1 |
        | Destination Address = 2001:db8::3   | SID[0] = 11       |
        |                                     | SID[1] = 3        |
        +-------------------------------------+-------------------+

        +-------------------------------------+-------------------+
        | As the packet travels from I3 to D: |                   |
        +-------------------------------------+-------------------+
        | Source Address = 2001:db8::a        | Segments Left = 0 |
        | Destination Address = 2001:db8::b   | SID[0] = 11       |
        |                                     | SID[1] = 3        |
        +-------------------------------------+-------------------+

A.3.  SR Path Contains Adjacency Segments Only

   In this example, Node S sends a packet to Node D, via two adjacency
   segments..

       +---------------------------------------+-------------------+
       | As the packet travels from S to I1:   |                   |
       +---------------------------------------+-------------------+
       | Source Address = 2001:db8::a          | Segments Left = 2 |
       | Destination Address = 2001:db8:0:1::2 | SID[0] = 129      |
       |                                       | SID[1] = 129      |
       +---------------------------------------+-------------------+









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       +---------------------------------------+-------------------+
       | As the packet travels from I1 to I3:  |                   |
       +---------------------------------------+-------------------+
       | Source Address = 2001:db8::a          | Segments Left = 1 |
       | Destination Address = 2001:db8:0:3::2 | SID[0] = 129      |
       |                                       | SID[1] = 129      |
       +---------------------------------------+-------------------+

       +---------------------------------------+-------------------+
       | As the packet travels from I3 to D:   |                   |
       +---------------------------------------+-------------------+
       | Source Address = 2001:db8::a          | Segments Left = 0 |
       | Destination Address = 2001:db8:0:b::2 | SID[0] = 129      |
       |                                       | SID[1] = 129      |
       +---------------------------------------+-------------------+

Authors' Addresses

   Ron Bonica
   Juniper Networks
   2251 Corporate Park Drive
   Herndon, Virginia  20171
   USA

   Email: rbonica@juniper.net


   Yuji Kamite
   NTT Communications Corporation
   3-4-1 Shibaura, Minato-ku
   Tokyo  108-8118
   Japan

   Email: : y.kamite@ntt.com


   Tomonobu Niwa
   KDDI
   3-22-7, Yoyogi, Shibuya-ku
   Tokyo  151-0053
   Japan

   Email: to-niwa@kddi.com








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Internet-Draft       IPv6 Compressed Routing Header       September 2019


   Andrew Alston
   Liquid Telecom
   Nairobi
   Kenya

   Email: Andrew.Alston@liquidtelecom.com


   Daniam Henriques
   Liquid Telecom
   Johannesburg
   South Africa

   Email: daniam.henriques@liquidtelecom.com


   Ning So
   Reliance Jio
   3010 Gaylord PKWY, Suite 150
   Frisco, Texas  75034
   USA

   Email: Ning.So@ril.com


   Fengman Xu
   Reliance Jio
   3010 Gaylord PKWY, Suite 150
   Frisco, Texas  75034
   USA

   Email: Fengman.Xu@ril.com


   Gang Chen
   Baidu
   No.10 Xibeiwang East Road Haidian District
   Beijing  100193
   P.R. China

   Email: phdgang@gmail.com










Bonica, et al.            Expires March 5, 2020                [Page 15]


Internet-Draft       IPv6 Compressed Routing Header       September 2019


   Yongqing Zhu
   China Telecom
   109 West Zhongshan Ave, Tianhe District
   Guangzhou
   P.R. China

   Email: zhuyq.gd@chinatelecom.cn


   Guangming Yang
   China Telecom
   109 West Zhongshan Ave, Tianhe District
   Guangzhou
   P.R. China

   Email: yanggm.gd@chinatelecom.cn


   Yifeng Zhou
   ByteDance
   Building 1, AVIC Plaza, 43 N 3rd Ring W Rd Haidian District
   Beijing  100000
   P.R. China

   Email: yifeng.zhou@bytedance.com


























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