MIP6 Working Group                                          Hee Jin Jang
Internet-Draft                                               Alper Yegin
Intended status: Standards Track                                 SAMSUNG
Expires: February 25, 2008                              Kuntal Chowdhury
                                                        Starent Networks
                                                          JinHyeock Choi
                                                                 SAMSUNG
                                                         August 24, 2007


          DHCP Option for Home Information Discovery in MIPv6
                      draft-ietf-mip6-hiopt-06.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
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   This Internet-Draft will expire on February 25, 2008.

Copyright Notice

   Copyright (C) The IETF Trust (2007).










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Abstract

   This draft defines a DHCP-based scheme to enable dynamic discovery of
   Mobile IPv6 home network information.  New DHCP options are defined
   which allow a mobile node to request the home agent IP address, FQDN,
   or home subnet prefix and obtain it via the DHCP response.


Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
   2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . . . .  4
   3.  DHCP options for HA Dynamic Discovery  . . . . . . . . . . . .  5
     3.1.  Home Network Identifier Option . . . . . . . . . . . . . .  5
     3.2.  MIP6 Relay Agent Option  . . . . . . . . . . . . . . . . .  7
       3.2.1.  MIP6 Relay Agent Sub-option  . . . . . . . . . . . . .  8
     3.3.  Home Network Information Option  . . . . . . . . . . . . .  9
       3.3.1.  Home Network Information Sub-option  . . . . . . . . . 11
   4.  Option Usage . . . . . . . . . . . . . . . . . . . . . . . . . 13
     4.1.  Mobile Node Behavior . . . . . . . . . . . . . . . . . . . 13
     4.2.  NAS/DHCP Relay Agent Behavior  . . . . . . . . . . . . . . 14
     4.3.  DHCP Server Behavior . . . . . . . . . . . . . . . . . . . 15
   5.  Security Considerations  . . . . . . . . . . . . . . . . . . . 18
   6.  IANA Consideration . . . . . . . . . . . . . . . . . . . . . . 19
   7.  Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 20
   8.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 21
     8.1.  Normative References . . . . . . . . . . . . . . . . . . . 21
     8.2.  Informative References . . . . . . . . . . . . . . . . . . 21
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 22
   Intellectual Property and Copyright Statements . . . . . . . . . . 23





















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1.  Introduction

   Before a mobile node can engage in Mobile IPv6 signaling with a home
   agent, it should either know the IP address of the home agent via
   pre-configuration, or dynamically discover it.  Mobile IPv6
   specification [RFC3775] describes how home agents can be dynamically
   discovered by mobile nodes that know the home subnet prefix.  This
   scheme does not work when prefix information is not already available
   to the mobile node.  This problem can be solved by delivering one or
   more home subnet prefix information to the mobile node by means of
   DHCP.  Subsequently, the mobile node can engage in dynamic home agent
   discovery using the prefix information.  In addition to delivering
   the prefix information, DHCP can also be used to provide the IP
   addresses or FQDNs of the home agents that are available to the
   mobile node.  The solution involves defining new DHCP options to
   carry home subnet prefix, home agent IP address and FQDN information.

   As part of configuring the initial TCP/IP parameters, a mobile node
   can obtain home network information for the subnet it is directly
   attached to, other subnets in the visited domain, or a subnet from
   its home domain.  A mobile node can indicate its home network
   identity when roaming to the visited network in order to obtain the
   MIP6 bootstrap parameters from the home network.  As an example, the
   visited network may determine the home network of the mobile node
   based on the realm portion of the NAI (Network Access Identifier)
   used in access authentication.

   The mobile node may or may not be connected to the "home" subnet when
   it attempts to learn Mobile IPv6 home network information.  This
   allows operators to centrally deploy home agents while being able to
   bootstrap mobile nodes that are already roaming.  This scenario also
   occurs when HMIPv6 [RFC4140] is used, where the mobile node is
   required to discover the MAP (a special home agent) that is located
   multiple hops away from the mobile node's attachment point.

















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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].

   General mobility terminology can be found in [RFC3753].  The
   following additional terms, as defined in [RFC4640], are used in this
   document:

   Access Service Provider (ASP): A network operator that provides
   direct IP packet forwarding to and from the mobile node.

   Mobility Service Provider (MSP): A service provider that provides
   Mobile IPv6 service.  In order to obtain such service, the mobile
   node must be authenticated and authorized to obtain the Mobile IPv6
   service.

   Mobility Service Authorizer (MSA): A service provider that authorizes
   Mobile IPv6 service.































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3.  DHCP options for HA Dynamic Discovery

   This section introduces new DHCP options used for dynamic home agent,
   FQDN, or home prefix information discovery in Mobile IPv6.  The
   drafts [I-D.ietf-mip6-radius] and
   [I-D.ietf-mip6-bootstrapping-integrated-dhc] describe the complete
   procedure for home agent assignment among the mobile node, NAS, DHCP,
   and AAA entities for bootstrapping procedure in the integrated
   scenario.

3.1.  Home Network Identifier Option

   This option is used to indicate the target home network requested by
   the mobile node to the DHCP server.  The mobile node MUST include
   this option along with its Option Request option in its request.




































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   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_MIP6-HNID        |           option-len          |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |     id-type   |    reserved   |    HNID_seq   |               |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+               +
  .                                                               .
  .                    Home Network Identifier                    .
  .                                                               .
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

        option-code

           OPTION_MIP6-HNID (TBD)

        option-len

           Total length of the option-data in octets

        id-type

           The type of Home Network Identifier:

               0    Visited domain (local ASP)

               1    Target MSP

               2    No preference

        reserved

           An 8-bit field reserved for future use.  The value MUST
           be initialized to 0 by the sender and MUST be ignored by
           the receiver.

        HNID_seq

           An 8-bit unsigned integer used for matching for Home Network
           Information options when the mobile node has requested with
           the multiple Home Network Identifier options with the same
           id-type 1 but having different Home Network Identifiers. The
           value starts from 1 and is increased incrementally.

        Home Network Identifier

           The identifier to specify the requested home network of
           the mobile node. This field MUST be set in the form of user's
           NAI [RFC4282].



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   The id-type 0 indicates the mobile node is interested in learning the
   home network information that pertains to the currently visited
   network.  This type can be used to discover local home agents in the
   local ASP.  In this case, the option-len field is set to 2 and the
   HNID_seq and the Home Network Identifier fields MUST not be included.

   The id-type 1 indicates the mobile node is interested in learning the
   home network information that pertains to the given realm.  This type
   can be used to discover home agents that are hosted by a user's home
   domain (MSA domain, as indicated by his/her NAI-based username
   --user@HomeRealm) or by any target domain.  The requested domain is
   specified in the Home Network Identifier field and can be a mobile
   node's home MSP or any MSP which has trust roaming relationship with
   the mobile node's MSA.

   If the mobile node has no preference, the id-type is set to 2.  The
   option-len field is set to 2 and the HNID_seq and the Home Network
   Identifier fields MUST not be included.  In this case, the assignment
   of the home network information is within the server's own
   discretion.  For the detailed processing, refer to section 4.

3.2.  MIP6 Relay Agent Option

   This option carries the RADIUS or Diameter attributes that are
   received at the NAS from the AAAH.  The DHCP relay agent sends this
   option to the DHCP server in the Relay-Forward message.


    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_MIP6-RELAY       |           option-len          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   .                          sub-options                          .
   .                                                               .
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

         option-code

            OPTION_MIP6-RELAY (TBD).

         option-len

            Total length of the option-data in octets

         sub-options
            A series of sub-options carrying MIP6 bootstrap
            information.




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3.2.1.  MIP6 Relay Agent Sub-option

   This sub-option carries the assigned home network information to the
   DHCP server.


    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |          sub-opt-code         |  sub-opt-len  |    reserved   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   .                                                               .
   .                   Home Network Information                    .
   .                                                               .
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

         sub-opt-code

            A 16-bit unsigned integer. The sub-option identifies the
            type of the following Home Network Information field.
            Possible values are:

                1    Home subnet prefix

                2    Complete IPv6 address of the home agent

                3    FQDN of the home agent

         sub-opt-len

            An 8-bit unsigned integer. The length of the following
            Home Network Information field + 1.

         reserved

            An 8-bit field reserved for future use.  The value MUST
            be initialized to 0 by the sender and MUST be ignored by
            the receiver.

         Home Network Information

            A home subnet prefix, home agent IP address or home agent
            FQDN to be provided to a mobile node according to the
            sub-opt-code.

   When the sub-opt-code is set to 1, the data field MUST contain the
   8-bit prefix length information followed by the 128-bit IPv6 address
   beginning with the available network prefix.




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   When the sub-opt-code is set to 2, the data field MUST contain the
   128-bit IPv6 address of the home agent.

   When the sub-opt-code is set to 3, the data field MUST contain the
   FQDN as described in [RFC1035].

   Multiple sub-options may exist in a MIP6 Relay Agent option to carry
   more than one home information.

3.3.  Home Network Information Option

   This option is used to carry home network information to a mobile
   node in the form of one or more of home subnet prefix(es), home agent
   address(es) and home agent FQDN(s).





































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    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_MIP6-HNINF       |           option-len          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     id-type   |    reserved   |    HNID_seq   |               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+               +
   .                          sub-options                          .
   .                                                               .
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

         option-code

            OPTION_MIP6-HNINF (TBD).

         option-len

            Total length of the option-data in octets

         id-type

            The type of Home Network Identifier:

                0    Visited domain (local ASP)

                1    Home domain

                2    No preference

         reserved

            An 8-bit field reserved for future use.  The value MUST
            be initialized to 0 by the sender and MUST be ignored by
            the receiver.

         HNID_seq

            An 8-bit unsigned integer used for matching for Home Network
            Identifier options when the mobile node has requested with
            the multiple Home Network Identifier options with the same
            id-type 1 but having different Home Network Identifiers.

         sub-options

            A series of sub-options carrying MIP6 bootstrap
            information.






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3.3.1.  Home Network Information Sub-option

   This sub-option carries the assigned home network information to the
   DHCP client.


    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |          sub-opt-code         |  sub-opt-len  |V|   reserved  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   .                                                               .
   .                   Home Network Information                    .
   .                                                               .
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

         sub-opt-code

            A 16-bit unsigned integer. The type of the following
            Home Network Information field. Possible values are:

                1    Home subnet prefix

                2    Complete IPv6 address of the home agent

                3    FQDN of the home agent

         sub-opt-len

            An 8-bit unsigned integer. The length of the following
            Home Network Information field + 1.

         V flag

            This flag specifies the location of home network where
            the home agent is assigned. If it is set to 1, it means
            that the following Home Network Information is allocated
            from the visited network.

         reserved

            A 7-bit field reserved for future use. The value MUST
            be initialized to 0 by the sender and MUST be ignored by
            the receiver.

         Home Network Information

            A home subnet prefix, home agent IP address or home agent
            FQDN to be provided to a mobile node according to the



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            sub-opt-code.


   The sub-opt-code, sub-opt-len and Home Network Information fields are
   set in the same manner as those of a MIP6 Relay Agent sub-option.

   Multiple sub-options may exist in a Home Network Information option
   to carry more than one home information.

   The detailed processing for each id-type is described in section 4.









































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4.  Option Usage

   The requesting and sending of the proposed DHCP options follow the
   rules for DHCP options in [RFC3315].  The following DHCP options
   [RFC3315] are also required in the solution for normal DHCP
   operation:

   - Option Request option

   - Client Identifier option

   - Relay Message option

   - Interface-Id option

4.1.  Mobile Node Behavior

   In order to acquire the home network information, the mobile node
   SHALL send an Information Request to the
   All_DHCP_Relay_Agents_and_Servers multicast address.  In this message
   the mobile node (DHCP client) SHALL include the Option Code for the
   Home Network Identifier option in the OPTION_ORO.  The mobile node
   SHALL also include the OPTION_CLIENTID [RFC3315] to identify itself
   to the DHCP server.

   During the process of requesting the bootstrapping information, the
   mobile node MUST clarify its preference about the requested home
   network with the id-type in the Home Network Identifier option.  Even
   though the mobile node does not care about the location of the home
   network where the home agent to be assigned, it MUST clarify the fact
   by setting the id-type to 2.

   The mobile node can request more than one home information by using
   multiple Home Network Identifier options in the request.  For
   instance, if the mobile node wants to retrieve home network
   information from both the visited network (ASP) and the home network
   with a single transaction, it can request the information by using
   two Home Network Identifier options with the id-type 0 and the id-
   type 1.  It can also request the home information for more than one
   target MSPs at the same time by including multiple Home Network
   Identifier options with the id-type 1.  However, there should not be
   more than one Home Network Identifier option with the id-type 0 or
   one Home Network Identifier option with the id-type 2 in the request.

   When the mobile node receives a Reply message from the DHCP server
   and gets more than one home network information, it MUST have a
   selection mechanism to determine which one to use for establishing a
   Mobile IPv6 session.  For example, if the mobile node acquires both



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   IPv6 address and FQDN of the home agent, it may try to use the
   address information of the home agent first.

   The Reply message may carry multiple home network Information.  When
   there are more than one Home Network Information option with the id-
   type 0 or one Home Network Information option with the id-type 2,
   only the first option is processed and the others are skipped.  When
   the Reply contains multiple Home Network Information options with the
   id-type 1, the mobile node should check each HNID_seq in the options
   in order to differentiate them and match each of them with the
   corresponding Home Network Identifier options correctly.  If the
   HNID_seq does not match with any of HNID_seq(s) of the Home Network
   Identifier in the request which has been sent previously, the Home
   Network Information option is ignored.

   When the mobile node has requested the home network information with
   the id-type 0 or 1 but cannot be provided with the proper
   information, that is, option-len = 0 in the Home Network Information
   option, then it may request again by setting the id-type to 2 in the
   Home Network Identifier option.

   In case a Home Network Information option carries the sub-option
   whose 'V' flag is not consistent with the id-type, the mobile node
   MUST skip the sub-option.

4.2.  NAS/DHCP Relay Agent Behavior

   The NAS and the DHCP relay agent are assumed to be collocated in this
   solution.  The NAS communicates with the mobile node during the
   network access authentication and interacts with the AAAH (via the
   AAAV) using either Diameter NASREQ [RFC4005] or RADIUS
   [I-D.ietf-mip6-radius] [Editor's note: The Diameter AVPs need to be
   defined].

   Upon receiving the MIP6 related RADIUS or Diameter attributes
   returned by the AAAH, the NAS passes the information to the
   collocated DHCP relay agent.

   Upon receiving the Information Request from the mobile node, the DHCP
   relay agent MUST forward the message to the DHCP server as per
   [RFC3315].  The relay agent SHALL use the OPTION_CLIENTID to identify
   the mobile node (user).  This is required to check whether there are
   some additional information for the user that need to be appended
   while relaying the information request message to the DHCP server.
   If the relay agent determines that the NAS has passed home network
   information for this mobile node, the relay agent MUST include the
   received home network information in the MIP6 Relay Agent option, and
   attach this option in the Relay-Forward message.  The relay agent MAY



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   include the Interface-Id option [RFC3315] in the Relay-Forward
   message.

   The sub-options that carry home information for the same home agent
   should be listed in sequential order of a sub-opt-code in the MIP6
   Relay Agent option so as to indicate the coupling among home network
   information for the same home agent.  For example, the sub-options
   for HA1 and HA2 are listed as follows.

   sub-opt-code = 2 (HA1's IPv6 address)

   sub-opt-code = 3 (HA1's FQDN)

   sub-opt-code = 1 (Home subnet prefix under HA2)

   sub-opt-code = 2 (HA2's IPv6 address)

   sub-opt-code = 3 (HA2's FQDN)

   Upon receiving a Reply message from the DHCPv6 server, the relay
   agent SHALL follow the guidelines defined in [RFC3315] to forward the
   message to the mobile node.

4.3.  DHCP Server Behavior

   The DHCP server MUST follow the following logic to process an
   Information Request from the mobile node.

   Information Request message includes:

   A. OPTION_ORO and Home Network Identifier option with the id-type 0,
   Interface-Id option, Client Identifier option, MIP6 Relay Agent
   option.

   If the DHCP server is configured with the local home information, it
   MUST include the corresponding information in the Home Network
   Information option of the Reply message, and set all of the V flag(s)
   in its sub-option(s) to 1(s).  The information may have been
   configured statically in the server.

   B. OPTION_ORO and Home Network Identifier option with the id-type 1,
   Interface-Id option, Client Identifier option, MIP6 Relay Agent
   option.

   If the received Home Network Identifier option does not carry any
   target MSP, the option MUST be ignored.

   If the DHCP server has the corresponding information for the target



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   MSP, it MUST include the information in the Home Network Information
   option, and set all of the V flag(s) in its sub-option(s) to 0(s).
   The server may provide the matching information extracted from the
   MIP6 Relay Agent option.

   C. OPTION_ORO and Home Network Identifier option with the id-type 2,
   Interface-Id option, Client Identifier option, MIP6 Relay Agent
   option.

   In this case, the assignment of the home information relies on the
   server's local policy, and the DHCP server SHOULD have its own policy
   so that it can reply with the proper information in the Home Network
   Information option.  The policy can be determined based on several
   factors such as the home agent availability and the authorization
   information of the mobile node.  However, the specific policy setting
   is not in the scope of this document.  The V flag(s) is/are set to
   0(s) or 1(s) according to the type of provided home network
   information.

   If the request message carries more than a Home Network Identifier
   option with the id-type 0 or a Home Network Identifier option with
   the id-type the id-type 2, only the first option is processed and the
   others are skipped.

   The DHCP server should provide all of the matching home information
   in Home Network Information option(s) based on its policy.  When the
   server has more than one home network information to provide for a
   single Home Network Identifier option, it SHOULD include each of them
   in Home Network Information sub-options and include these sub-options
   in a single Home Network Information option.  The sub-options for the
   same home agent SHOULD be listed in sequential order of a sub-opt-
   code in the Home Network Information option as described in section
   4.2.

   There SHOULD not be more than a Home Network Information option with
   the id-type 0 or a Home Network Information option with the id-type 2
   in the reply.  When there are multiple Home Network Identifier
   options with the same id-type 1 but having the different Home Network
   Identifiers, the server should copy the HNID_seq in the Home Network
   Identifier option to the corresponding Home Network Information
   options.  In case of id-type 0 and 2, the HNID_seq value is
   initialized to 0.

   Though the server cannot find any home information for a specific id-
   type, it MUST return the Home Network Information option by setting
   the id-type to the requested id-type and the option-len to 0.

   In all Reply messages, the DHCP server MUST return the Interface-Id



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   option as received in the Information Request.  The DHCP server
   SHOULD use the Client Identifier option to identify the mobile node.

   There can be various ways that a DHCP server learns mechanism to know
   or retrieve the requested home network information.  For instance, as
   described in [I-D.ietf-mip6-radius], the NAS can learn the
   information via RADIUS during network access authentication, and NAS-
   collocated DHCP relay can transfer it to the DHCP server by the
   proposed DHCP option in this document.  However, the mechanism by
   which the DHCP server is provisioned with the home network
   information or obtains it dynamically is outside the scope of this
   document.







































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5.  Security Considerations

   Secure delivery of home agent and home network information from a
   DHCP server to the mobile node (DHCP client) relies on the same
   security as DHCP.  The particular option defined in this draft does
   not have additional impact on DHCP security.

   Aside from the DHCP client to server interaction, an operator must
   also ensure secure delivery of mobile IP information to the DHCP
   server.  This is outside the scope of DHCP and the newly defined
   option.








































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6.  IANA Consideration

   This document defines three new DHCPv6 options, Home Network
   Identifier option, MIP6 Relay Agent option and Home Network
   Information option.

   IANA is requested to assign the following new DHCPv6 Option Codes in
   the registry maintained in
   http://www.iana.org/assignments/dhcpv6-parameters:

       o OPTION_MIP6-HNID for the Home Network Identifier option
       o OPTION_MIP6-RELAY for the MIP6 Relay Agent option
       o OPTION_MIP6-HNINF for the Home Network Information option






































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7.  Acknowledgements

   The authors would like to thank Kilian Weniger, Domagoj Premec,
   Basavaraj Patil, Vijay Devarapalli, Gerardo Giaretta, Behcet
   Sarikaya, Vidya Narayanan and Miguel A. Diaz for their valuable input
   and comments.













































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8.  References

8.1.  Normative References

   [I-D.ietf-mip6-bootstrapping-integrated-dhc]
              Chowdhury, K. and A. Yegin, "MIP6-bootstrapping for the
              Integrated Scenario",
              draft-ietf-mip6-bootstrapping-integrated-dhc-05 (work in
              progress), July 2007.

   [I-D.ietf-mip6-radius]
              Chowdhury, K., "RADIUS Mobile IPv6 Support",
              draft-ietf-mip6-radius-02 (work in progress), March 2007.

   [RFC1035]  Mockapetris, P., "Domain names - implementation and
              specification", STD 13, RFC 1035, November 1987.

   [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.

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

   [RFC4005]  Calhoun, P., Zorn, G., Spence, D., and D. Mitton,
              "Diameter Network Access Server Application", RFC 4005,
              August 2005.

   [RFC4282]  Aboba, B., Beadles, M., Arkko, J., and P. Eronen, "The
              Network Access Identifier", RFC 4282, December 2005.

8.2.  Informative References

   [RFC3753]  Manner, J. and M. Kojo, "Mobility Related Terminology",
              RFC 3753, June 2004.

   [RFC4140]  Soliman, H., Castelluccia, C., El Malki, K., and L.
              Bellier, "Hierarchical Mobile IPv6 Mobility Management
              (HMIPv6)", RFC 4140, August 2005.

   [RFC4640]  Patel, A. and G. Giaretta, "Problem Statement for
              bootstrapping Mobile IPv6 (MIPv6)", RFC 4640,
              September 2006.





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Authors' Addresses

   Hee Jin Jang
   Samsung Advanced Institute of Technology
   P.O. Box 111
   Suwon 440-600
   Korea

   Email: heejin.jang@samsung.com


   Alper E. Yegin
   Samsung Electronics
   Istanbul
   Turkey

   Email: alper01.yegin@partner.samsung.com


   Kuntal Chowdhury
   Starent Networks
   30 International Place
   Tewksbury, MA  01876
   US

   Email: kchowdhury@starentnetworks.com


   JinHyeock Choi
   Samsung Advanced Institute of Technology
   P.O. Box 111
   Suwon 440-600
   Korea

   Email: athene@sait.samsung.co.kr
















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Full Copyright Statement

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