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6man                                                           R. Bonica
Internet-Draft                                          Juniper Networks
Intended status: Standards Track                               Y. Kamite
Expires: October 5, 2020                  NTT Communications Corporation
                                                                 T. Niwa
                                                                    KDDI
                                                               A. Alston
                                                          Liquid Telecom
                                                                L. Jalil
                                                                 Verizon
                                                           April 3, 2020


                The IPv6 Compressed Routing Header (CRH)
                   draft-bonica-6man-comp-rtg-hdr-14

Abstract

   This document defines two new Routing header types.  Collectively,
   they are called the Compressed Routing Headers (CRH).  Individually,
   they are called CRH-16 and CRH-32.

Status of This Memo

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

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

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

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

Copyright Notice

   Copyright (c) 2020 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



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   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  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Requirements Language . . . . . . . . . . . . . . . . . . . .   3
   3.  The Compressed Routing Headers (CRH)  . . . . . . . . . . . .   3
   4.  The CRH  Forwarding Information Base (CRH-FIB)  . . . . . . .   5
   5.  Processing Rules  . . . . . . . . . . . . . . . . . . . . . .   6
     5.1.  Computing Minimum CRH Length  . . . . . . . . . . . . . .   7
   6.  Mutability  . . . . . . . . . . . . . . . . . . . . . . . . .   8
   7.  Applications And SIDs . . . . . . . . . . . . . . . . . . . .   8
   8.  Management Considerations . . . . . . . . . . . . . . . . . .   9
   9.  ICMPv6 Considerations . . . . . . . . . . . . . . . . . . . .   9
   10. Security Considerations . . . . . . . . . . . . . . . . . . .   9
   11. Implementation and Deployment Status  . . . . . . . . . . . .   9
   12. IANA Considerations . . . . . . . . . . . . . . . . . . . . .  10
   13. Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  10
   14. Contributors  . . . . . . . . . . . . . . . . . . . . . . . .  10
   15. References  . . . . . . . . . . . . . . . . . . . . . . . . .  11
     15.1.  Normative References . . . . . . . . . . . . . . . . . .  11
     15.2.  Informative References . . . . . . . . . . . . . . . . .  12
   Appendix A.  CRH Processing Examples  . . . . . . . . . . . . . .  12
   Appendix B.  CRH Processing Examples  . . . . . . . . . . . . . .  13
     B.1.  The SID List Contains One Entry For Each Segment In The
           Path  . . . . . . . . . . . . . . . . . . . . . . . . . .  14
     B.2.  The SID List Omits The First Entry In The Path  . . . . .  15
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  15

1.  Introduction

   IPv6 [RFC8200] source nodes use Routing headers to specify the path
   that a packet takes to its destination.  The IETF has defined several
   Routing header types [IANA-RH].  RH0 [RFC2460] was the first to be
   defined and was deprecated [RFC5095] because of security
   vulnerabilities.

   This document defines two new Routing header types.  Collectively,
   they are called the Compressed Routing Headers (CRH).  Individually,
   they are called CRH-16 and CRH-32.

   The CRH, like RH0, allows IPv6 source nodes to specify the path that
   a packet takes to its destination.  The CRH differs from RH0 because:




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   o  It can be encoded in fewer bytes than RH0.

   o  It addresses the security vulnerabilities that affected RH0.

   The following are reasons for encoding the CRH in as few bytes as
   possible:

   o  Many ASIC-based forwarders copy all headers from buffer memory to
      on-chip memory.  As header sizes increase, so does the cost of
      this copy.

   o  Because Path MTU Discovery (PMTUD) [RFC8201] is not entirely
      reliable, many IPv6 hosts refrain from sending packets larger than
      the IPv6 minimum link MTU (i.e., 1280 bytes).  When packets are
      small, the overhead imposed by large Routing Headers is excessive.

   Section 10 of this document addresses security considerations.
   Appendix A of this document demonstrates how the CRH can be encoded
   in fewer bytes than RH0.

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 Headers (CRH)

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

   o  Next Header - Defined in [RFC8200].

   o  Hdr Ext Len - Defined in [RFC8200].

   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].

   o  Type-specific Data - Described in [RFC8200].

   In the CRH, the Type-specific data field contains a list of Segment
   Identifiers (SIDs).  Each SID represents both of the following:




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   o  A segment of the path that the packet takes to its destination.

   o  An entry in the CRH Forwarding Information Base (CRH-FIB)
      (Section 4).

   SIDs are listed in reverse order.  So, the first SID in the list
   represents the final segment in the path.  Because segments are
   listed in reverse order, the Segments Left field can be used as an
   index into the SID list.  In this document, the "current SID" is the
   SID list entry referenced by the Segments Left field.

   The first segment in the path can be omitted from the list.  See
   (Appendix B) for examples.

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

   In all cases, the CRH MUST end on a 64-bit boundary.  So, the Type-
   specific data field MUST be padded with zeros if the CRH would
   otherwise not end on a 64-bit boundary.

        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

















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       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 CRH Forwarding Information Base (CRH-FIB)

   Each SID identifies a CRH-FIB entry.

   Each CRH-FIB entry contains:

   o  A IPv6 address.

   o  A forwarding method.

   o  Method-specific parameters (optional).

   The IPv6 address represents an interface on the next segment
   endpoint.  It MUST NOT be a link-local address.  While the IPv6
   address represents an interface on the next segment endpoint, it does
   not necessarily represent the interface through which the packet will
   arrive at the next segment endpoint.

   The forwarding method specifies how the processing node will forward
   the packet to the next segment endpoint.  The following are examples:

   o  Forward the packet to the next-hop along the least-cost path to
      the next segment endpoint.

   o  Forward the packet through a specified interface to the next
      segment endpoint.

   Some forwarding methods require method-specific parameters.  For
   example, a forwarding method might require a parameter that
   identifies the interface through which the packet should be
   forwarded.



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   The CRH-FIB can be populated:

   o  By an operator, using a Command Line Interface (CLI).

   o  By a controller, using the Path Computation Element (PCE)
      Communication Protocol (PCEP) [RFC5440] or the Network
      Configuration Protocol (NETCONF) [RFC6241].

   o  By a distributed routing protocol [ISO10589-Second-Edition],
      [RFC5340], [RFC4271].

5.  Processing Rules

   The following rules apply to packets that contain a CRH:

   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 the IPv6 Destination Address is a link-local address, discard
      the packet.

   o  If the IPv6 Hop Limit is less than or equal to 1, discard the
      packet and send an ICMPv6 Time Exceeded message to the Source
      Address.

   The following rules describe CRH processing:

   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 5.1)).

   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 Segments Left.






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   o  Search for the current SID in the CRH-FIB.  In this document, the
      "current SID" is the SID list entry referenced by the Segments
      Left field.

   o  If the search does not return a CRH-FIB 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 CRH-FIB entry contains a link-local address, discard the
      packet and send an ICMPv6 Parameter Problem, Code 0, message to
      the Source Address, pointing to the current SID.

   o  If Segments Left is greater than 0 and the CRH-FIB entry contains
      a multicast address, discard the packet and send an ICMPv6
      Parameter Problem, Code 0, message to the Source Address, pointing
      to the current SID.

   o  Copy the IPv6 address from the CRH-FIB entry to the Destination
      Address field in the IPv6 header.

   o  Decrement the IPv6 Hop Limit.

   o  Resubmit the packet to the IPv6 module for transmission to the new
      destination, ensuring that it executes the forwarding method
      specified by the CRH-FIB entry.

5.1.  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.














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             <CODE BEGINS>

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

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

             return(words)


             <CODE ENDS>


6.  Mutability

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

7.  Applications And SIDs

   A CRH contains one or more SIDs.  Each SID is processed by exactly
   one node.

   Therefore, a SID is not required to have domain-wide significance.
   Applications can:

   o  Allocate SIDs so that they have domain-wide significance.

   o  Allocate SIDs so that they have node-local significance.








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8.  Management Considerations

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

9.  ICMPv6 Considerations

   Implementations MUST comply with the ICMPv6 processing rules
   specified in Section 2.4 of [RFC4443].  For example:

   o  An implementation MUST NOT originate an ICMPv6 error message in
      response to another ICMPv6 error message.

   o  An implementation MUST rate limit the ICMPv6 messages that it
      originates.

10.  Security Considerations

   Networks that process the CRH MUST mitigate the security
   vulnerabilities described in [RFC5095].  Their border routers SHOULD
   discard packets that satisfy the following criteria:

   o  The packet contains a CRH

   o  The Segments Left field in the CRH has a value greater than 0

   o  The Destination Address field in the IPv6 header represents an
      interface that resides inside of the network.

   Many border routers cannot filter packets based upon the Segments
   Left value.  These border routers MAY discard packets that satisfy
   the following criteria:

   o  The packet contains a CRH

   o  The Destination Address field in the IPv6 header represents an
      interface that resides inside of the network.

11.  Implementation and Deployment Status

   Juniper Networks has produced experimental implementations of the CRH
   on:

   o  A LINUX-based software platform

   o  The MX-series (ASIC-based) router





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   Liquid Telecom has deployed the CRH, on a limited basis, in their
   network.  Other experimental deployments are in progress.

12.  IANA Considerations

   SID values 0-15 are reserved for future use.  They may be assigned by
   IANA, based on IETF Consensus.  IANA is requested to establish a
   "Registry of SRm6 Reserved SIDs".  Values 0-15 are reserved for
   future use.

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

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

13.  Acknowledgements

   Thanks to Dr. Vanessa Ameen, Fernando Gont, Naveen Kottapalli, Joel
   Halpern, Tony Li, Gerald Schmidt, Nancy Shaw, and Chandra Venkatraman
   for their contributions to this document.

14.  Contributors

      Daniam Henriques

      Liquid Telecom

      Johannesburg, South Africa

      Email: daniam.henriques@liquidtelecom.com



      Gang Chen

      Baidu

      No.10 Xibeiwang East Road Haidian District

      Beijing 100193 P.R.  China

      Email: phdgang@gmail.com




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      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

15.  References

15.1.  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>.

   [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>.

   [RFC5095]  Abley, J., Savola, P., and G. Neville-Neil, "Deprecation
              of Type 0 Routing Headers in IPv6", RFC 5095,
              DOI 10.17487/RFC5095, December 2007,
              <https://www.rfc-editor.org/info/rfc5095>.

   [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>.

   [RFC8201]  McCann, J., Deering, S., Mogul, J., and R. Hinden, Ed.,
              "Path MTU Discovery for IP version 6", STD 87, RFC 8201,
              DOI 10.17487/RFC8201, July 2017,
              <https://www.rfc-editor.org/info/rfc8201>.








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15.2.  Informative References

   [IANA-RH]  IANA, "Routing Headers",
              <https://www.iana.org/assignments/ipv6-parameters/
              ipv6-parameters.xhtml#ipv6-parameters-3>.

   [ISO10589-Second-Edition]
              International Organization for Standardization,
              ""Intermediate system to Intermediate system intra-domain
              routeing information exchange protocol for use in
              conjunction with the protocol for providing the
              connectionless-mode Network Service (ISO 8473)", ISO/IEC
              10589:2002, Second Edition,", November 2001.

   [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>.

   [RFC2460]  Deering, S. and R. Hinden, "Internet Protocol, Version 6
              (IPv6) Specification", RFC 2460, DOI 10.17487/RFC2460,
              December 1998, <https://www.rfc-editor.org/info/rfc2460>.

   [RFC4271]  Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A
              Border Gateway Protocol 4 (BGP-4)", RFC 4271,
              DOI 10.17487/RFC4271, January 2006,
              <https://www.rfc-editor.org/info/rfc4271>.

   [RFC5340]  Coltun, R., Ferguson, D., Moy, J., and A. Lindem, "OSPF
              for IPv6", RFC 5340, DOI 10.17487/RFC5340, July 2008,
              <https://www.rfc-editor.org/info/rfc5340>.

   [RFC5440]  Vasseur, JP., Ed. and JL. Le Roux, Ed., "Path Computation
              Element (PCE) Communication Protocol (PCEP)", RFC 5440,
              DOI 10.17487/RFC5440, March 2009,
              <https://www.rfc-editor.org/info/rfc5440>.

   [RFC6241]  Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
              and A. Bierman, Ed., "Network Configuration Protocol
              (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
              <https://www.rfc-editor.org/info/rfc6241>.

Appendix A.  CRH Processing Examples

   The CRH-16 and CRH-32 encode information more efficiently than RH0.






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                     +------+-----+--------+--------+
                     | SIDs | RH0 | CRH-16 | CRH-32 |
                     +------+-----+--------+--------+
                     |  1   |  24 |   8    |   8    |
                     |  2   |  40 |   8    |   16   |
                     |  3   |  56 |   16   |   16   |
                     |  4   |  72 |   16   |   24   |
                     |  5   |  88 |   16   |   24   |
                     |  6   | 104 |   16   |   32   |
                     |  7   | 120 |   24   |   32   |
                     |  8   | 136 |   24   |   40   |
                     |  9   | 152 |   24   |   40   |
                     |  10  | 168 |   24   |   48   |
                     |  11  | 184 |   32   |   48   |
                     |  12  | 200 |   32   |   52   |
                     |  13  | 216 |   32   |   52   |
                     |  14  | 232 |   32   |   56   |
                     |  15  | 248 |   40   |   56   |
                     |  16  | 264 |   40   |   60   |
                     |  17  | 280 |   40   |   60   |
                     |  18  | 296 |   40   |   64   |
                     +------+-----+--------+--------+

     Table 1: Routing Header Size (in Bytes) As A Function Of Routing
                      Header Type and Number Of SIDs

   (Table 1) reflects Routing header size as a function of Routing
   header type and number of SIDs contained by the Routing header.

Appendix B.  CRH Processing Examples

   This appendix demonstrates CRH processing in the following scenarios:

   o  The SID list contains one entry for each segment in the path
      (Appendix B.1).

   o  The SID list omits the first entry in the path (Appendix B.2).














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    -----------                 -----------                 -----------
   |Node: S    |               |Node: I1   |               |Node: I2   |
   |Loopback:  |---------------|Loopback:  |---------------|Loopback:  |
   |2001:db8::a|               |2001:db8::1|               |2001:db8::2|
    -----------                 -----------                 -----------
         |                                                       |
         |                      -----------                      |
         |                     |Node: D    |                     |
          ---------------------|Loopback:  |---------------------
                               |2001:db8::b|
                                -----------

                       Figure 3: Reference Topology

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

                +-----+--------------+-------------------+
                | SID | IPv6 Address | Forwarding Method |
                +-----+--------------+-------------------+
                | 2   | 2001:db8::2  | Least-cost path   |
                | 11  | 2001:db8::b  | Least-cost path   |
                +-----+--------------+-------------------+

                            Table 2: Node SIDs

   Table 2 describes two entries that appear in each node's CRH-FIB.

B.1.  The SID List Contains One Entry For Each Segment In The Path

   In this example, Node S sends a packet to Node D, via I2.  In this
   example, I2 appears in the CRH segment list.

        +-------------------------------------+-------------------+
        | As the packet travels from S to I2: |                   |
        +-------------------------------------+-------------------+
        | Source Address = 2001:db8::a        | Segments Left = 1 |
        | Destination Address = 2001:db8::2   | SID[0] = 11       |
        |                                     | SID[1] = 2        |
        +-------------------------------------+-------------------+

        +-------------------------------------+-------------------+
        | As the packet travels from I2 to D: |                   |
        +-------------------------------------+-------------------+
        | Source Address = 2001:db8::a        | Segments Left = 0 |
        | Destination Address = 2001:db8::b   | SID[0] = 11       |
        |                                     | SID[1] = 2        |
        +-------------------------------------+-------------------+




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B.2.  The SID List Omits The First Entry In The Path

   In this example, Node S sends a packet to Node D, via I2.  In this
   example, I2 does not appear in the CRH segment list.

        +-------------------------------------+-------------------+
        | As the packet travels from S to I2: |                   |
        +-------------------------------------+-------------------+
        | Source Address = 2001:db8::a        | Segments Left = 1 |
        | Destination Address = 2001:db8::2   | SID[0] = 11       |
        +-------------------------------------+-------------------+

        +-------------------------------------+-------------------+
        | As the packet travels from I2 to D: |                   |
        +-------------------------------------+-------------------+
        | Source Address = 2001:db8::a        | Segments Left = 0 |
        | Destination Address = 2001:db8::b   | SID[0] = 11       |
        +-------------------------------------+-------------------+

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           April 2020


   Andrew Alston
   Liquid Telecom
   Nairobi
   Kenya

   Email: Andrew.Alston@liquidtelecom.com


   Luay Jalil
   Verizon
   Richardson, Texas
   USA

   Email: luay.jalil@one.verizon.com





































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