Network Working Group                                           D. Damic
Internet-Draft                                                 D. Premec
Intended status: Standards Track                                B. Patil
Expires: August 28, 2008                                 M. Sahasrabudhe
                                                  Nokia Siemens Networks
                                                             S. Krishnan
                                                                Ericsson
                                                       February 25, 2008


               Proxy Mobile IPv6 indication and discovery
              draft-damic-netlmm-pmip6-ind-discover-03.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.

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   This Internet-Draft will expire on August 28, 2008.

Copyright Notice

   Copyright (C) The IETF Trust (2008).

Abstract

   Proxy Mobile IPv6 is a network-based mobility protocol that enabes
   mobility management for an IP host as it moves across different
   points of attachment within the mobility domain.  An IP host whose
   mobility is being managed by the network is unaware of the access



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   networks capability to do mobility management on its behalf using
   Proxy Mobile IPv6.  This draft proposes mechanisms by which the host
   is informed of Proxy Mobile IPv6 support, as well as how to actively
   discover such capability in the network that host attaches to.  The
   ability of the host to discover or be aware of Proxy Mobile IPv6
   support in the access network enables better decision making in terms
   of the network selection and attach procedure as well as the choice
   of mobility management.


Table of Contents

   1.  Introduction and Scope . . . . . . . . . . . . . . . . . . . .  3
   2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . . . .  4
   3.  Problem Statement  . . . . . . . . . . . . . . . . . . . . . .  4
   4.  Proposed Solutions . . . . . . . . . . . . . . . . . . . . . .  5
     4.1.  PMIP6 indication in the Router Advertisment  . . . . . . .  5
     4.2.  Alternate Prefix Information Option  . . . . . . . . . . .  6
     4.3.  Router Solicitation Client-based Mobility Flag . . . . . .  9
     4.4.  DHCPv6 extensions  . . . . . . . . . . . . . . . . . . . . 10
       4.4.1.  Home Network Identifier Option . . . . . . . . . . . . 10
       4.4.2.  Home Network Information Option  . . . . . . . . . . . 12
       4.4.3.  Note on DHCPv4 . . . . . . . . . . . . . . . . . . . . 13
   5.  Security Considerations  . . . . . . . . . . . . . . . . . . . 13
   6.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 13
   7.  Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 13
   8.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 14
     8.1.  Normative References . . . . . . . . . . . . . . . . . . . 14
     8.2.  Informative References . . . . . . . . . . . . . . . . . . 14
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15
   Intellectual Property and Copyright Statements . . . . . . . . . . 17




















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1.  Introduction and Scope

   Proxy Mobile IPv6 [I-D.ietf-netlmm-proxymip6] is a network-based
   mobility management protocol which does not require any signaling
   from the mobile node to enable IP mobility as the node moves and
   changes its point of attachment.  PMIP6 is based on Mobile IPv6
   [RFC3775] principles albeit the fact that the host is not involved in
   the mobility management.  A Mobile IPv6 capable host may choose not
   to have the network perform mobility management on its behalf, via
   Proxy Mobile IPv6, in some scenarios.

   PMIP6 protocol as specified in [I-D.ietf-netlmm-proxymip6] is
   applicable within the scope of a single PMIP6 domain.  However
   deployment scenarios may include a broader scope than a single
   domain.
   Scenarios where mobility is managed by the network are usually
   referred to as running in Proxy MIP (PMIP) mode.  Analogously, when
   mobile nodes manage mobility themselves we are talking about host-
   based mobility.  There are several scenarios in which host-based
   Mobile IP and Proxy MIP support co-exist in the same network.  Two
   cases are described below, and a more exhaustive interactions
   analysis can be found in [I-D.giaretta-netlmm-mip-interactions]:

   o  Simultaneous support for different mobility modes:
      The operator may need to support mobility services for hosts which
      may not include MIP client functionality, as well as those
      implementing Mobile IP within the same PMIP6 domain.  Discovery of
      the capabilities of the host and the network enables appropriate
      services to be triggered for all types of hosts.

   o  Session continuation accros different domains:
      Mobile node roaming in/out of the PMIP6 domain aims to continue
      the ongoing session either retaining or substituting the assigned
      mobility mode.  For example, MN running a MIP6 session in the
      network moves to a PMIP6-enabled domain.  Depending on the
      privileges and policies, the session may either continue by using
      host-based mobility, or the network would take over the mobility
      management and begin handling the MN in the PMIP6 mode.

   Existing IPv6 mechanisms, such as Neighbor Discovery protocol (NDP)
   or DHCPv6, are currently insufficient for the purpose of mobility
   mode detection or capability negotiation.  This document proposes
   means by which the network can advertise PMIP6 capability and service
   being provided in the network, and provide specific configuration
   parameters to mobile nodes.  The proposal also provides a method by
   which the MN can proactively participate in mobility mode selection
   by sending the explicit mode indication.




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2.  Terminology

   The keywords "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].

   PMIP6 prefix
   Prefix assigned to the MN while residing within the PMIP6 domain.
   The prefix is topologically anchored at the LMA, thus providing IP
   session continuity all throughout that LMA domain.  Depending on the
   mobility scope, this prefix can be assigned by the LMA or some other
   mechanism.

   Local (on-link) prefix
   Topologically correct IPv6 prefix available for address
   autoconfiguration within the local domain, for example valid within a
   scope of a single AR/MAG.


3.  Problem Statement

   A host which attaches to a network which is a part of a PMIP6 domain
   may use stateless address autoconfiguration (SLAAC) or DHCPv6 to
   configure its addresses.  The type of prefix advertised to the host
   or configuration parameters returned to it may vary depending on
   variables such as policy, host preference, host capability etc.

   In case PMIP6 is used as a mechanism for managing mobility or for
   emulating the home link to the MN, the network obtains the home
   prefix for the MN and provides the same to the MN.  Prefix is
   assigned to the MN for the entire session, and must be consistently
   advertised throughout the entire PMIP6 domain.  For MIP6 capable
   nodes it is sufficient to supply any globallly routable local prefix/
   address that the MN will use to configure the care-of address (CoA)
   on its interface.

   At the point when network allocates the address/prefix for the given
   mobile, or the Access Router begins advertising the specific IPv6
   prefix information the network is unaware of the capability of the MN
   which is attempting to attach to the AR:
   NDP and DHCP messages as defined today cannot serve as specific PMIP6
   mobility triggers.  Furthermore, the profile associated with a user
   in AAA in not sufficient for deciding about the mobility protocol for
   that MN as the device and terminal capabilities may change.  For
   example: Profile or policy parameters associated with a subscriber
   authorizing PMIP6 service cannot be used in triggering network
   mobility since the capability of the host or preference cannot be
   determined.



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   The AR or MAG in the access network should anticipate different types
   of IPv6 mobility services and terminals, and make sure the correct
   service is assigned to the mobile node.  The network should take into
   account mobility preference of the mobile, in case such information
   is provided beforehand, in the router solicitation (RS) or a DHCP
   request.

   Explicit mechanisms and protocol extensions are needed to:
   o  enable the access network to advertise the PMIP6 support to the MN
   o  provide the MN with more reliable parameters allowing it to choose
      the mobility protocol based on its capabilities or other criteria
   o  allow MNs to indicate their mobility mode preferences


4.  Proposed Solutions

   This document proposes extensions to the NDP and DHCPv6 protocols
   that may serve as triggers for PMIP6 mobility selection.  The
   proposed extensions include: a new indication flag in the RA, new
   prefix information option for the Router Advertisement, flag
   extention to the Router Solicitation messages, as well as
   modifications for the related DHCPv6 MIP6 bootstrap extensions.

4.1.  PMIP6 indication in the Router Advertisment

   As per [RFC5075] the AR should use the Flags Expansion option to
   further extend the flags field of the Router Advertisement message.
   This memo proposes the AR SHOULD use this RA expansion option to
   explicitly indicate mobility managemenet capabilities of the access
   nework.  By setting the "N" flag in the Flags Expansion option, AR
   advertises its capability for network-based mobility management
   (i.e., PMIP6 support).


          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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Type      |    Length     |N|       Bit fields available ..
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      ... for assignment                                              |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

       Figure 1. RA Flags Expansion option with the PMIP6 indication








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   Type

      Type - 8-bit identifier of the option type
      To be assigned by IANA, as indicated in [RFC5075]

   Length

      Length = 1; The length MUST be checked when processing the option
      in order to allow for future expansion of this option if the need
      arises.

   Bits

      Router Advertisement bit 8 - the "N" flag
      (To be assigned by IANA.)  This bit is set by the AR to indicate
      the access network supports network-based mobility management,
      i.e., PMIP6.  Other bits are available for further assignment.


4.2.  Alternate Prefix Information Option

   The AR is allowed to include multiple IPv6 prefixes in the single RA
   message where each prefix is contained in an own Prefix Information
   Option [RFC4861].  In case the access network supports PMIP6, the AR
   MAY chose to simultaneoulsy advertise local on-link IPv6 prefixes, as
   well as the individual PMIP6 prefix for that MN.  For this specific
   case, the two different types of prefixes SHOULD be cleary
   differentiated.

   The Alternate Prefix Information Option shall provide host with
   additional prefix information for the purpose of stateless IPv6
   address autoconfiguration.  In case the network supports multiple
   mobility service types, the AR may provide alternative option to the
   mobile node leaving the choice of the mobility service to the
   terminal.
   In order to make use of the service indication and selection, the MN
   has to be enhanced for processing of the new Alternate Prefix
   Information option.  Mobile nodes that are capable of processing the
   Alternate Prefix Information option should use the obtained
   information according to internal configuration and policy to decide
   whether to configure PMIP6 MN-HoA or MIP6 CoA on its network
   interface.  Node incapable of understanding the Alternate Prefix
   option SHALL ignore it.

   The format of the option supports regular operation and backwards
   compatibility for all legacy terminals by allowing flexibility in
   prefix assignment.  Depending on the network policy and capabilities,
   the AR can advertise on-link prefixes, or the PMIP6 prefix as default



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   information within the Prefix Information Option.  By specifying the
   Prefix Type, the alternative prefix information can then be provided
   in the new option.


   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Type      |    Length     | Prefix Length |L|A|   |Pr.Type|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                         Valid Lifetime                        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                       Preferred Lifetime                      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                           Reserved                            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   +                                                               +
   |                                                               |
   +                         IPv6 Prefix                           +
   |                                                               |
   +                                                               +
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

               Figure 2. Alternate Prefix Information Option

   Fields:

   Type

      8-bit identifier for the Alternate Prefix Information option (to
      be assigned by IANA).

   Length  4

   Prefix Length

      8-bit unsigned integer.  The number of leading bits in the Prefix
      that are valid.  The value ranges from 0 to 128.

   L

      1-bit on-link flag.  Use of the flag as defined in [RFC4861]: When
      set, indicates this prefix can be used for on-link determination,
      when not set the advertisement makes no statement about on-link or
      off-link properties of the prefix. .




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   A

      1-bit autonomous address-configuration flag.  When set indicates
      that this prefix can be used for stateless address configuration
      as specified in [RFC4862].

   Prefix Type

      4-bit unsigned field.  The field indicates the type of the prefix
      provided in the payload.  Allowed values:
      0    On-link IPv6 prefix bound to the first hop AR
      1    PMIPv6 prefix anchored at the associated LMA

   Valid Lifetime

      32-bit unsigned integer.  The length of time in seconds (relative
      to the time the packet is sent) that the prefix is valid for the
      purpose of on-link determination.  A value of all one bits
      (0xffffffff) represents infinity.  The Valid Lifetime is also used
      by [RFC4862].

   Preferred Lifetime

      32-bit unsigned integer.  The length of time in seconds (relative
      to the time the packet is sent) that addresses generated from the
      prefix via stateless address autoconfiguration remain preferred.
      A value of all one bits (0xffffffff) represents infinity.  See
      [RFC4862].

   Reserved

      This field is unused.  It MUST be initialized to zero by the
      sender and MUST be ignored by the receiver.

   IPv6 Prefix

      An IPv6 address or a prefix of an IPv6 address.  The length of the
      prefix is given by the Prefix Length field, and the purpose of the
      prefix is defined by the Prefix Type field.  A router SHOULD NOT
      send a prefix option for the link-local prefix and a host SHOULD
      ignore such a prefix option.


   Description:
   The Alternate Prefix Information option provides host with an
   additional prefix information for stateless address
   autoconfiguration.  Respective of the prefix already provided in the
   regular Prefix, this option may contain either the topologically



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   correct on-link prefix (type set to 0), or the PMIPv6 prefix (type 1)
   for the purpose of establishing network-based mobility management.
   The option appears in Router Advertisement packets only and MUST be
   silently ignored for other messages.


4.3.  Router Solicitation Client-based Mobility Flag

   If a mobile node that chooses or prefers to do its own mobility
   signaling enters a PMIPv6 network it cannot do so since the PMIP
   domain makes the MN believe that it is in fact in its home network.
   This section describes a mechanism by which a mobile node in a PMIPv6
   network can signal to the PMIPv6 network whether it would like to
   make use of the Proxy Mobility service or not.  This document
   modifies the format of the Router Solicitation Message specified in
   [RFC4861] to include a new client-based mobility flag.  As a result
   of this the router solicitation message format will look like the
   following figure:

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Type      |     Code      |          Checksum             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |C|                          Reserved                           |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |   Options ...
      +-+-+-+-+-+-+-+-+-+-+-+-

      Figure 3. Client-based mobility flag in the Router Solicitation

   ICMP Fields:

   Type  133

   Code  0

   Checksum

      The ICMP checksum.  See [RFC4443]

   C

      If this bit is set, it means that the sending MN would like to
      perform its own signaling.






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   Reserved

      This field is unused.  It MUST be initialized to zero by the
      sender and MUST be ignored by the receiver.


   A mobile node that utilises this mechanism and wants to perform its
   own signaling, MUST set the C bit to one.  The MAG that receives it
   SHOULD respond with a Router Advertisement containing a topologically
   correct prefix for the link (i.e., Not the emulated PMIPv6 prefix).
   MNs which are not aware of this specification will not set the C bit
   and hence the MAG would provide them with proxy mobility service.
   MAGs not aware of this bit when a client sets the C bit to 1 will
   ignore it as specified in [RFC4861].  Hence there are no backward
   compatibility issues

4.4.  DHCPv6 extensions

   This section describes how a mobile node can use DHCP [RFC3315] to
   detect that it is located in the PMIP domain and to inform the AR of
   its preference to use PMIP6 or host-based MIP6 as a mobility
   management protocol.

   By using DHCP, mobile node and the AR are able to exchange following
   information:
   o  AR can let the mobile node know that the access network supports
      the PMIP6 protocol
   o  AR can inform the mobile node of the PMIP6 prefix
   o  mobile node can inform the AR wheather it should provide a PMIP6
      service to it or if the MN prefers to run MIP6 by itself

   Draft [I-D.ietf-mip6-hiopt] defines new DHCPv6 options used to
   facilitate bootstraping of a MIP6 based mobility service.  One of the
   options introduced by the draft is a Home Network Identifier option
   (OPTION_MIP6-HNID) by which the mobile node can request information
   about the home network and indicate its preference for the location
   of the HA: in the visited network or in the target network.

4.4.1.  Home Network Identifier Option

   The Home Network Identifier option is extended with an additional
   code to allow the mobile node to explicitely request information
   about the availability of the PMIP service at its current point of
   attachment.







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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   |   sequence #  |                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
      .                                                               .
      .                    Home Network Identifier                    .
      .                                                               .
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

              Figure 4. Home Network Identifier option format

   option-code

      OPTION_MIP6-HNID (TBD)

   option-len

      Total length of the option in octets

   id-type

      The type of Home Network Identifier:
      0    Visited domain (local ASP)
      1    The target network
      2    No preference
      3    PMIP domain

   When the mobile node wants to learn if the access network supports
   PMIP6 service, it SHALL include Home Network Option setting the id-
   type field to 3.  When the id-type is set to 3, the Home Network
   Identifier field MAY be set to 0 if the mobile node wants to learn
   about the PMIP6 support in the local domain.  Alternatively, if the
   mobile node wants to inquire about the support for PMIP6 service in a
   particular network, the mobile node MAY set the Home Network
   Identifier field to the network realm as FQDN.

   The mobile node can learn information about a particular network type
   by sending separate Information Request messages with different id-
   types.  If the mobile node wants to acquire the information about the
   visited network, target network and the PMIP6 domain in a single
   message exchange, it MAY include several Home Network Identifier
   options in the reguest message.  There may be several Home Network
   Identifier options with the id-type 1 and/or 3 in a single message.






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4.4.2.  Home Network Information Option

   Draft [I-D.ietf-mip6-hiopt] defines a new DHCPv6 option Home Network
   Information option.  This option is used by the DHCP server to convey
   to the mobile node information about inquired network(s).  The
   information provided could be a home subnet prefix (one or more),
   home agent address(es) and home agent FQDN(s).  There is a separate
   suboption for each type of information provided (prefix, home agent
   address and home agent FQDN).

   If the id-type field of the Home Network Identifier option indicates
   the network which is not supported by this access network or if the
   mobile node is not authorized for the requested network, the DHCP
   server's reponse SHALL include the Home Network Information option
   with the option-len set to zero.

   If the mobile node inquiered information about the PMIP domain, the
   relevant information about the PMIP domain will be provided in the
   Home Network Information option.  In this case the only relevant
   information is prefix.  Since in PMIP mode the mobile node does not
   interact with the home agent directly, home agent's address and FQDN
   SHALL not be provided to the mobile node.

   If the access network wants to force the PMIP mode for the mobile
   node, it MAY respond to both visited domain and target domain(s)
   inquieris with a Home Network Information option containing the
   0-length data.

4.4.2.1.  Avoiding the premature prefix advertisment

   When the netlmm domain supports the DHCP extensions specified here,
   the AR may want to defer advertisment of the prefix until both the
   mobile node and network have exchanged their capabilites and
   preferences for a mobility management mode.  This can be achived by
   setting the 'M' or 'O' flag in Router Advertisment message forcing
   the mobile node to use DHCP.  In this way the AR can delay the prefix
   advertisment until the DHCP exchange is completed.

4.4.2.2.  Choosing the PMIP mode

   If the client decides that it would use PMIP6 service offered by the
   access network, it SHALL send the (additional) Information Request
   message containing Home Network Information sub-option with the Home
   Network Information field containing the PMIP network prefix.







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4.4.3.  Note on DHCPv4

   Home Network Identifier option and Home Network Information option
   defined for DHCPv6 could be adopted, with some modifications, for
   DHCPv4.  This would enable the single stack IPv4 host to become aware
   of the PMIP service support by the access network.  Wheather the
   approach of adopting the DHCPv6 options for DHCPv4 is feasible in
   this particular case is for futher study.

   The IPv4 host would include the Home Network Identifier option,
   indicating its preferences, in the DHCPDISCOVER message.  DHCPOFFER
   message would include Home Network Information option indicating the
   network type(s) supported by the access network and authorized for
   the mobile node.  The mobile node would indicate its choice in the
   DHCPREQUEST message by including the Home Network Information option
   with the id-type field set to the selected network type.


5.  Security Considerations

   The mechanisms described in this document use neighbor discovery
   messages to communicate mobility preferences and indications between
   the MN and the network.  An on-link attacker can send spoofed router
   advertisements and spoofed router solicitation in order to deny
   mobility service to the node.  The usage of SEND [RFC3971] could
   prevent this from happening.


6.  IANA Considerations

   The following Extension Types MUST be assigned by IANA:

   o  PMIP6 "N" indication flag in RA flags expansion option
   o  Alternate Prefix Information Option type
   o  Client-based mobility flag for RS message
   o  DHCPv6 Home Network Information Option (id-type 3 PMIP)


7.  Acknowledgements

   TBD.


8.  References







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8.1.  Normative References

   [I-D.ietf-mip6-hiopt]
              Jang, H., Yegin, A., Chowdhury, K., and J. Choi, "DHCP
              Options for Home Information Discovery in MIPv6",
              draft-ietf-mip6-hiopt-11 (work in progress),
              February 2008.

   [I-D.ietf-netlmm-proxymip6]
              Gundavelli, S., Leung, K., Devarapalli, V., Chowdhury, K.,
              and B. Patil, "Proxy Mobile IPv6",
              draft-ietf-netlmm-proxymip6-11 (work in progress),
              February 2008.

   [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.

   [RFC4443]  Conta, A., Deering, S., and M. Gupta, "Internet Control
              Message Protocol (ICMPv6) for the Internet Protocol
              Version 6 (IPv6) Specification", RFC 4443, March 2006.

   [RFC4861]  Narten, T., Nordmark, E., Simpson, W., and H. Soliman,
              "Neighbor Discovery for IP version 6 (IPv6)", RFC 4861,
              September 2007.

   [RFC4862]  Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless
              Address Autoconfiguration", RFC 4862, September 2007.

   [RFC5075]  Haberman, B. and R. Hinden, "IPv6 Router Advertisement
              Flags Option", RFC 5075, November 2007.

8.2.  Informative References

   [I-D.giaretta-netlmm-mip-interactions]
              Giaretta, G., "Interactions between PMIPv6 and MIPv6:
              scenarios and related issues",
              draft-giaretta-netlmm-mip-interactions-02 (work in
              progress), November 2007.

   [RFC3971]  Arkko, J., Kempf, J., Zill, B., and P. Nikander, "SEcure
              Neighbor Discovery (SEND)", RFC 3971, March 2005.



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Authors' Addresses

   Damjan Damic
   Nokia Siemens Networks
   Heinzelova 70a
   Zagreb  10000
   Croatia

   Phone: +385 1 6331 337
   Email: damjan.damic.ext@nsn.com


   Domagoj Premec
   Nokia Siemens Networks
   Heinzelova 70a
   Zagreb  10000
   Croatia

   Phone: +385 1 6105 923
   Email: domagoj.premec.ext@nsn.com


   Basavaraj Patil
   Nokia Siemens Networks
   6000 Connection Drive
   Irving, TX  75039
   US

   Phone:
   Email: basavaraj.patil@nsn.com


   Meghana Sahasrabudhe
   Nokia Siemens Networks
   313 Fairchild Drive
   Mountain View, CA  94043
   US

   Phone:
   Email: meghana.sahasrabudhe@nsn.com











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Internet-Draft    draft-damic-netlmm-pmip6-ind-discover    February 2008


   Suresh Krishnan
   Ericsson
   8400 Decarie Blvd.
   Town of Mount Royal, QC
   Canada

   Phone: +1 514 345 7900 x42871
   Email: suresh.krishnan@ericsson.com











































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