One document matched: draft-dupont-ikev2-haassign-00.txt

Network Working Group                                     F. Dupont, Ed.
Internet-Draft                                                    Point6
Expires: May 18, 2006                                  November 14, 2005


  IKEv2-based Home Agent Assignment in Mobile IPv6/NEMO Bootstrapping
                   draft-dupont-ikev2-haassign-00.txt

Status of this Memo

   By submitting this Internet-Draft, each author represents that any
   applicable patent or other IPR claims of which he or she is aware
   have been or will be disclosed, and any of which he or she becomes
   aware will be disclosed, in accordance with Section 6 of BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF), its areas, and its working groups.  Note that
   other groups may also distribute working documents as Internet-
   Drafts.

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

   The list of current Internet-Drafts can be accessed at
   http://www.ietf.org/ietf/1id-abstracts.txt.

   The list of Internet-Draft Shadow Directories can be accessed at
   http://www.ietf.org/shadow.html.

   This Internet-Draft will expire on May 18, 2006.

Copyright Notice

   Copyright (C) The Internet Society (2005).

Abstract

   This document specifies how to use IKEv2 for Home Agent assignment in
   Mobile IPv6 or NEMO bootstrapping.  It uses anycast addresses and
   should not introduce new security issues.


1.  Introduction

   Home Agent (HA) assignment is an improvement over HA discovery: in
   place of giving a list of possible HA addresses, this procedure gives



Dupont                    Expires May 18, 2006                  [Page 1]

Internet-Draft          IKEv2-based HA Assignment          November 2005


   the HA to use in a way controlled by the Mobile Service Provider, for
   (initial) load balancing, fail-over or DoS avoidance.

   IKEv2 [IKEv2] is the tool of choice in bootstrapping scenarios
   because not only it established the needed Security Associations but
   it can allocate home Addresses, authenticate the Mobile Node (MN)
   using EAP [RFC2284], etc [IKEv2-MIPv6].  The only function it did not
   support is the HA assignment.

   This document addresses both Mobile IPv6 [RFC3775] and NEMO [RFC3963]
   cases, the second likely with another anycast address.

   The goal of the document is to provide HA assignment support using an
   IKEv2 initial message sent to an anycast destination address without
   introduction of new security issues.

   This document could use the standard keywords [BCP14] to indicate
   requirement levels.


2.  The proposal

   In the IKEv2 exchanges, the MN takes the initiator role and the HA
   the responder role.  The MN takes parameters from its configuration,
   followed or not by a discovery phase.  The HA address is a
   recognizable anycast address.  So:
   1.  the MN sends an IKE_SA_INIT request to the HA anycast address
   2.  the anycast receiver forwards the request to the "best" HA
   3.  the HA answers using its own address as the source address and
       includes an "under attack" cookie in its replies
   4.  the MN notes the HA address to use in subsequent messages and
       retries the IKE_SA_INIT request with the cookie to the HA own
       address
   The standard IKEv2 procedure follows...

   The proposal can be used in any environment, including Mobile IPv6
   and NEMO, as soon as a recognizable anycast address is assigned to
   the provided service (cf. IANA (Section 3)).

   The term "recognizable anycast address" means an anycast address
   which is recognizable as an anycast address by the initiator.  This
   includes, but not exclusively, addresses in the subnet anycast
   address format defined by [RFC2526].


3.  IANA Considerations

   Mobile IPv6 defines an IPv6 subnet anycast address [RFC2526] (value



Dupont                    Expires May 18, 2006                  [Page 2]

Internet-Draft          IKEv2-based HA Assignment          November 2005


   decimal=126 / hexa=7E).  In the case Mobile IPv6 and NEMO services
   are not provided by the same HAs, a second anycast address has to be
   assigned by IANA for NEMO HAs.


4.  Security Considerations

   As the anycast address can be well known, the cookie-based defense
   against DoS is used by default.  Another advantage is the whole
   IKE_SA_INIT and IKE_AUTH exchanges are performed using the "right"
   addresses so the impact of the proposal on IKEv2 implementations can
   be kept minimal.

   As in the standard IKEv2 ([IKEv2] section 2.4 4th paragraph) the
   initiator has to reject cryptographically invalid fake IKE_SA_INIT
   replies so there is no new attack against the initiator side.


5.  Acknowledgments

   The initial idea was in a Kilian Weniger's message about HA
   assignment.  Jean-Michel Combes, speaking for a Mobile IPv6/NEMO
   operator, insisted to improve the current HA discovery to HA
   assignment.  Kero Kivinen checked whether the proposal introduces new
   security issue and whether it is reasonably easy to implement.


6.  References

6.1.  Normative References

   [BCP14]    Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", RFC 2119, BCP 14, March 1997.

   [IKEv2]    Kaufman, C., Ed., "Internet Key Exchange (IKEv2)
              Protocol", draft-ietf-ipsec-ikev2-17.txt (work in
              progress), September 2004.

   [RFC2526]  Johnson, D. and S. Deering, "Reserved IPv6 Subnet Anycast
              Addresses", RFC 2526, March 1999.

   [RFC3775]  Johnson, D., Perkins, C., and J. Arkko, "Mobility Support
              in IPv6", RFC 3775, June 2004.

   [RFC3963]  Devarapalli, V., Wakikawa, R., Petrescu, A., and P.
              Thubert, "Network Mobility (NEMO) Basic Support Protocol",
              RFC 3963, January 2005.




Dupont                    Expires May 18, 2006                  [Page 3]

Internet-Draft          IKEv2-based HA Assignment          November 2005


6.2.  Informative References

   [IKEv2-MIPv6]
              Devarapalli, V. and F. Dupont, "Mobile IPv6 Operation with
              IKEv2 and the revised IPsec",
              draft-ietf-mip6-ikev2-ipsec-04.txt (work in progress),
              October 2005.

   [RFC2284]  Blunk, L. and J. Vollbrecht, "PPP Extensible
              Authentication Protocol (EAP)", RFC 2284, March 1998.









































Dupont                    Expires May 18, 2006                  [Page 4]

Internet-Draft          IKEv2-based HA Assignment          November 2005


Author's Address

   Francis Dupont (editor)
   Point6
   c/o GET/ENST Bretagne
   2 rue de la Chataigneraie
   CS 17607
   35576 Cesson-Sevigne Cedex
   France

   Fax:   +33 2 99 12 70 30
   Email: Francis.Dupont@enst-bretagne.fr







































Dupont                    Expires May 18, 2006                  [Page 5]

Internet-Draft          IKEv2-based HA Assignment          November 2005


Intellectual Property Statement

   The IETF takes no position regarding the validity or scope of any
   Intellectual Property Rights or other rights that might be claimed to
   pertain to the implementation or use of the technology described in
   this document or the extent to which any license under such rights
   might or might not be available; nor does it represent that it has
   made any independent effort to identify any such rights.  Information
   on the procedures with respect to rights in RFC documents can be
   found in BCP 78 and BCP 79.

   Copies of IPR disclosures made to the IETF Secretariat and any
   assurances of licenses to be made available, or the result of an
   attempt made to obtain a general license or permission for the use of
   such proprietary rights by implementers or users of this
   specification can be obtained from the IETF on-line IPR repository at
   http://www.ietf.org/ipr.

   The IETF invites any interested party to bring to its attention any
   copyrights, patents or patent applications, or other proprietary
   rights that may cover technology that may be required to implement
   this standard.  Please address the information to the IETF at
   ietf-ipr@ietf.org.


Disclaimer of Validity

   This document and the information contained herein are provided on an
   "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
   OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
   ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
   INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
   INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
   WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.


Copyright Statement

   Copyright (C) The Internet Society (2005).  This document is subject
   to the rights, licenses and restrictions contained in BCP 78, and
   except as set forth therein, the authors retain all their rights.


Acknowledgment

   Funding for the RFC Editor function is currently provided by the
   Internet Society.




Dupont                    Expires May 18, 2006                  [Page 6]