The IPv6 Segment Endpoint Option
draft-bonica-6man-seg-end-opt-01

#x27;s source and its destination.

5.  Option Processing

   If the option appears in a Hop-by-hop Options header, the processing
   node discards the packet and sends an ICMPv6 [RFC4443] Parameter
   Problem, Code 2, message to the packet's Source Address, pointing to
   the Segment Endpoint option Type.

   If the option appears in a Destination Options header, the processing
   node locates the following fields in Option Data:

   o  Segments Left.

   o  Containers.

   o  Container List.

   It then processes each member of the Container List as follows:

   o  Locate the Segment ID and IPv6 Option field in the container.

   o  If Segments Left less than the Segment ID, skip over the
      container.

   o  If Segments Left equals the Segment ID, and the IPv6 Option is a
      Segment Endpoint option, skip over the container.

   o  If Segments Left equals the Segment ID, and the IPv6 Option is not
      a Segment Endpoint option, process the IPv6 Option as per
      [RFC8200].

   o  If Segments Left is greater than Segment ID, skip over all
      remaining members of the Container List.

   Finally, decrement the Segment ID field and process the next option
   or header.

Bonica, et al.          Expires September 7, 2019               [Page 5]
Internet-Draft           Segment Endpoint Option              March 2019

6.  Mutability

   The Segments Left field of the Segment Endpoint option is mutable.
   Intermediate nodes MAY change the value of this field.

   All other fields in the Segment Endpoint option are immutable.
   Intermediate nodes MUST NOT change the values of these fields.

7.  Security Considerations

   The Segment Endpoint Option shares many security concerns with IPv6
   routing headers.  In particular, any boundary filtering protecting a
   domain from external routing headers should also protect against
   external Segment Endpoint Options being processed inside a domain.
   This occurs naturally if encapsulation is used to add routing headers
   to a packet.  If external routing headers are allowed, then
   protections must also include ensuring that any provided Segment
   Endpoint option before the routing header is properly protect, e.g.
   with an IPSEC AH header or other suitable means.

   As with Routing headers, the security assumption within a domain is
   that the domain is trusted to provide, and to avoid improperly
   modifying, the Segment Endpoint Option.

8.  IANA Considerations

   IANA is requested to allocate a codepoint from the Destination
   Options and Hop-by-hop Options registry
   (https://www.iana.org/assignments/ipv6-parameters/
   ipv6-parameters.xhtml#ipv6-parameters-2).  This option is called
   "Segment Endpoint".  The "act" bits are 10 and the "chg" bit is 1.

9.  Acknowledgements

   Thanks to TBD for their careful review of this document.

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>.

Bonica, et al.          Expires September 7, 2019               [Page 6]
Internet-Draft           Segment Endpoint Option              March 2019

   [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>.

10.2.  Informative References

   [IPv6-OPT]
              IANA, ""Destination Options and Hop-by-Hop Options"",
              August 1987, <https://www.iana.org/assignments/ipv6-
              parameters/ipv6-parameters.xhtml#ipv6-parameters-2>.

Authors' Addresses

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

   Email: rbonica@juniper.net

   Joel Halpern
   Ericsson
   P. O. Box 6049
   Leesburg, Virginia  20178
   USA

   Email: joel.halpern@ericsson.com

Bonica, et al.          Expires September 7, 2019               [Page 7]
Internet-Draft           Segment Endpoint Option              March 2019

Gang Chen
Baidu
Baidu Technology Park Building No.2, No.10 Xibeiwang East Road Haidian District
Beijing  100193
P.R. China

Email: phdgang@gmail.com

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

   Email: zhuyq.gd@chinatelecom.cn

Bonica, et al.          Expires September 7, 2019               [Page 8]