Network Working Group                                            G. Zorn
Internet-Draft                                               Network Zen
Intended status: Standards Track                                   Q. Wu
Expires: February 5, 2011                                        Y. Wang
                                                                  Huawei
                                                          August 4, 2010


                  The Local Domain Name DHCPv6 Option
                   draft-ietf-hokey-ldn-discovery-03

Abstract

   In order to derive a Domain-Specific Root Key (DSRK) from the
   Extended Master Session Key (EMSK) generated as a side-effect of an
   Extensible Authentication Protocol (EAP) method, the EAP peer must
   discover the name of the domain to which it is attached.

   This document specifies a Dynamic Host Configuration Protocol Version
   6 (DHCPv6) option designed to allow a DHCPv6 server to inform clients
   of the name of the local domain..

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
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   This Internet-Draft will expire on February 5, 2011.

Copyright Notice

   Copyright (c) 2010 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
   (http://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  . . . . . . . . . . . . . . . . . . . . . . . . . 3
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . 3
   3.  Option Format . . . . . . . . . . . . . . . . . . . . . . . . . 3
     3.1.  DHCPv6 Local Domain Name Option . . . . . . . . . . . . . . 3
   4.  Appearance of the Option  . . . . . . . . . . . . . . . . . . . 4
   5.  Client Behavior . . . . . . . . . . . . . . . . . . . . . . . . 4
   6.  Relay Agent Behavior  . . . . . . . . . . . . . . . . . . . . . 4
   7.  Server Behavior . . . . . . . . . . . . . . . . . . . . . . . . 4
   8.  Security Considerations . . . . . . . . . . . . . . . . . . . . 4
   9.  IANA considerations . . . . . . . . . . . . . . . . . . . . . . 5
   10. References  . . . . . . . . . . . . . . . . . . . . . . . . . . 5
     10.1. Normative References  . . . . . . . . . . . . . . . . . . . 5
     10.2. Informative References  . . . . . . . . . . . . . . . . . . 5






























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1.  Introduction

   The EAP Re-authentication Protocol (ERP) [RFC5296] is designed to
   allow faster re-authentication of a mobile device which was
   previously authenticated by means of the Extensible Authentication
   Protocol (EAP, [RFC3748].  Given that the local root key (e.g., DSRK
   RFC 5295 [RFC5295]) is generated using the local domain name (LDN),
   LDN discovery is an important part of re-authentication.  As
   described in RFC 5296 [RFC5296], the local domain name can be learned
   by the mobile device through the ERP exchange or via a lower-layer
   mechanism.  However, no lower-layer mechanisms for LDN discovery have
   yet been defined.

   This document specifies an extension to DHCPv6 for local domain name
   discovery.

2.  Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].

3.  Option Format

   In DHCPv6-based local domain name discovery, the LDN option is used
   by the DHCPv6 client (MD) to obtain the local domain name from the
   DHCPv6 Server after full EAP authentication has taken place.

3.1.  DHCPv6 Local Domain Name Option

   The format of this option is:

   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | OPTION_LOCAL_DOMAIN_NAME      |         option-length         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             local-domain-name ...
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                                 Figure 1

   option code  OPTION_LOCAL_DOMAIN_NAME (TBD)

   option-length  Length of the 'local domain name' field in octets






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   local-domain-name  This field contains the name of the local domain
      and MUST be encoded as specified in Section "8 of RFC 3315
      [RFC3315]

4.  Appearance of the Option

   The LDN option MUST NOT appear in DHCPv6 messages other than the
   types Solicit, Advertise, Request, Information-Request and Reply.
   The option-code of the LDN option MAY be included in the Option
   Request Option in the DHCPv6 message types Solicit, Request and
   Information-Request.

5.  Client Behavior

   If a DHCPv6 client (MD) doesn't know the local domain name and
   requires the DHCPv6 Server to provide the DHCPv6 LDN option, it MUST
   include an Option Request option requesting the DHCPv6 LDN option, as
   described in Section 22.7 of RFC 3315 [RFC3315].

   When the DHCPv6 client recieves a LDN option with the local domain
   name present in it, it MUST verify that the option length is no more
   than 256 octets (the maximum length of a single FQDN allowed by DNS),
   and that the local domain name is a properly encoded single FQDN, as
   specified in Section 8, "Representation and Use of Domain Names" of
   RFC3315 [RFC3315].

6.  Relay Agent Behavior

   If a DHCPv6 relay agent has pre-existing knowledge of the local
   domain name (for example, from a previous AAA exchange), it SHOULD
   include it in the DHCPv6 LDN option and forward to the DHPv6 server.

7.  Server Behavior

   If the option code for the LDN option is included in an Option
   Request option, the server SHOULD return the DHCPv6 LDN option to the
   client.  If a DHCPv6 LDN option is received from a relay agent with a
   non-empty local-domain-name field, the server SHOULD extract this
   option and include it in the reply message.

8.  Security Considerations

   The communication between the DHCPv6 client and the DHCPv6 server for
   the exchange of local domain name information is security sensitive
   and requires authentication, integrity and replay protection.  Either
   lower-layer security (such as link layer security established as part
   of the network access authentication protocol run) or DHCP security
   [RFC3118] can be used.



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9.  IANA considerations

   IANA is requested to allocate one DHCPv6 Option code, referencing
   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, March 1997.

   [RFC3315]  Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C.,
              and M. Carney, "Dynamic Host Configuration Protocol for
              IPv6 (DHCPv6)", RFC 3315, July 2003.

   [RFC5295]  Salowey, J., Dondeti, L., Narayanan, V., and M. Nakhjiri,
              "Specification for the Derivation of Root Keys from an
              Extended Master Session Key (EMSK)", RFC 5295,
              August 2008.

   [RFC5296]  Narayanan, V. and L. Dondeti, "EAP Extensions for EAP Re-
              authentication Protocol (ERP)", RFC 5296, August 2008.

10.2.  Informative References

   [RFC3118]  Droms, R. and W. Arbaugh, "Authentication for DHCP
              Messages", RFC 3118, June 2001.

   [RFC3748]  Aboba, B., Blunk, L., Vollbrecht, J., Carlson, J., and H.
              Levkowetz, "Extensible Authentication Protocol (EAP)",
              RFC 3748, June 2004.

Authors' Addresses

   Glen Zorn
   Network Zen
   77/440 Soi Phoomjit, Rama IV Road
   Phra Khanong, Khlong Toie
   Bangkok  10110
   Thailand

   Phone: +66 (0) 87 502 4274
   EMail: gwz@net-zen.net







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   Qin Wu
   Huawei Technologies Co., Ltd.
   Site B, Floor 12, Huihong Mansion, No.91 Baixia Rd.
   Nanjing, Jiangsu  21001
   China

   Phone: +86-25-84565892
   EMail: sunseawq@huawei.com


   Yungui Wang
   Huawei Technologies Co., Ltd.
   Site B, Floor 10, HuiHong Mansion, No.91 BaiXia Rd.
   Nanjing, Jiangsu  210001
   P.R. China

   Phone: +86 25 84565893
   EMail: w52006@huawei.com

































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