NETEXT WG                                                  S. Gundavelli
Internet-Draft                                                     Cisco
Intended status: Standards Track                             J. Korhonen
Expires: July 5, 2012                             Nokia Siemens Networks
                                                              M. Grayson
                                                                K. Leung
                                                           R. Pazhyannur
                                                                   Cisco
                                                         January 2, 2012


      Access Network Identifier (ANI) Option for Proxy Mobile IPv6
             draft-ietf-netext-access-network-option-03.txt

Abstract

   This specification defines a mechanism and a related mobility option
   for carrying the access network identifier and the access operator
   identification information from the mobile access gateway to the
   local mobility anchor over Proxy Mobile IPv6.  Based on the received
   information, the local mobility anchor is able to provide access
   network and access operator specific handling or policing for the
   mobile node traffic.

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
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   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."

   This Internet-Draft will expire on July 5, 2012.

Copyright Notice

   Copyright (c) 2012 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



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   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   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.  Conventions and Terminology  . . . . . . . . . . . . . . . . .  4
     2.1.  Conventions  . . . . . . . . . . . . . . . . . . . . . . .  4
     2.2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . .  4
   3.  Access Network Identifier Option . . . . . . . . . . . . . . .  5
     3.1.  Access Network Identifier Sub-Option . . . . . . . . . . .  6
     3.2.  Network-Identifier Sub-Option  . . . . . . . . . . . . . .  6
     3.3.  Geo-Location ANI Sub-Option  . . . . . . . . . . . . . . .  7
     3.4.  Operator-Identifier Sub-Option . . . . . . . . . . . . . .  8
   4.  Protocol Considerations  . . . . . . . . . . . . . . . . . . .  9
     4.1.  Mobile Access Gateway Considerations . . . . . . . . . . .  9
     4.2.  Local Mobility Anchor Considerations . . . . . . . . . . . 11
   5.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 11
   6.  Protocol Configuration Variables . . . . . . . . . . . . . . . 12
   7.  Security Considerations  . . . . . . . . . . . . . . . . . . . 13
   8.  Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 13
   9.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 14
     9.1.  Normative References . . . . . . . . . . . . . . . . . . . 14
     9.2.  Informative References . . . . . . . . . . . . . . . . . . 14
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 14




















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1.  Introduction

   In many deployments there is a need for the local mobility anchor to
   provide differentiated services and policing to the mobile nodes
   based on the access network to which they are attached.  Policy
   systems in mobility architectures such as PCC [TS23203] and ANDSF
   [TS23402] in 3GPP system allow configuration of policy rules with
   conditions based on the access network information.  For example, the
   service treatment for the mobile node's traffic may be different when
   they are attached to a access network owned by the home operator than
   when owned by a roaming partner.  The service treatment can also be
   different based on the configured Service Set Identifiers (SSID) in
   case of IEEE 802.11 based access networks.

   The Proxy Mobile IPv6 specification [RFC5213] allows for carrying the
   Access Technology Type (ATT) information from the mobile access
   gateway (MAG) to the local mobility anchor (LMA).  However, the
   Access Technology Type alone is not necessarily sufficient for a
   suitable policy to be applied at the LMA.  Therefore, there is a need
   for an additional access network related information to be available
   at the LMA.  Learning the access network operator identity may not be
   possible for an LMA without a support of an additional policy
   framework that is able to provide required information out of band to
   the LMA.  Such a policy framework may not be required for all Proxy
   Mobile IPv6 deployments and hence an alternative approach for
   carrying such information is required to ensure that additional
   information related to the access network is available.

   This document defines a new mobility option, Access Network
   Identifier (ANI) option for Proxy Mobile IPv6 (PMIPv6), that can be
   used by mobile access gateway for carrying the access network
   information to the local mobility anchor.  The specific details on
   how the local mobility anchor uses this information is out-of-scope
   for this document.

   Figure 1 illustrates an example PMIPv6 deployment where the mobile
   access gateway delivers the information elements related to the
   access network to the local mobility anchor over Proxy Mobile IPv6
   signaling messages.  In this example, the additional information
   could comprise the used SSID of the used IEEE 802.11 network, the
   geo-location of the access points, and the identities of the
   operators running the IEEE 802.11 access network infrastructure.









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       SSID: IETF-1
       Geo-location: 37o49'11"N 122o28'43"W
       Operator-Id: provider1.example.com
       +--+
       |AP|-------.                        {Access Specific Policies)
       +--+       |             _-----_             |
                +-----+       _(       )_        +-----+
                | MAG |-=====(   PMIPv6  )======-| LMA |-
                +-----+       (_ Tunnel_)        +-----+
       +--+       |             '-----'
       |AP|-------'
       +--+
       SSID: IETF-2
       Geo-location: 59o19'40.21"N  18o 3'18.36"E
       Operator-Id: provider2.example.com

                 Figure 1: Access Networks attached to MAG


2.  Conventions and Terminology

2.1.  Conventions

   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 RFC 2119 [RFC2119].

2.2.  Terminology

   All the mobility related terms used in this document are to be
   interpreted as defined in the Proxy Mobile IPv6 specifications
   [RFC5213] and [RFC5844].  Additionally, this document uses the
   following abbreviations:

   Service Set Identifier

      Service Set Identifier (SSID) identifies the name of the IEEE
      802.11 network.  SSID differentiates from one network to the
      other.

   Vendor ID

      The Vendor ID is the SMI Network Management Private Enterprise
      Code of the IANA-maintained Private Enterprise Numbers registry
      [SMI].






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   ANDSF

      Access Network Discovery and Selection Function.

   PCC

      Policy and Charging Control Framework.


3.  Access Network Identifier Option

   The Access Network Identifier mobility option is used to exchanged
   access network related information between a local mobility anchor
   and a mobile access gateway.  The option can be included in both
   Proxy Binding Update (PBU) and Proxy Binding Acknowledgement (PBA)
   messages, and there can only be a single instance of this mobility
   option in a mobility message.  The Access Network Identifier mobility
   option always contains one or more Access Network Identifier Sub-
   options.  The Access Network Identifier Sub-option is described in
   Section 3.1.

   The alignment requirement for this option is 4n.


    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      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
                  ...      ANI Sub-option(s) ...                   ~
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


                Figure 2: Access Network Identifier Option

   Type:  (IANA-1)

   Length:  8-bit unsigned integer indicating the length in octets of
      the option, excluding the type and length fields.

   If the local mobility anchor understands the Access Network
   Identifier mobility option received in a PBU and also agrees with the
   sub-option(s) content defined in this specification, then the local
   mobility anchor MUST echo the Access Network Identifier mobility
   option back to a mobile access gateway in a PBA.  The Access Network
   Identifier sub-options defined in this specification MUST NOT be
   altered by the local mobility anchor.  Future specification utilizing
   Access Network Identifier mobility option MAY define use cases and



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   new sub-options that can purposely be altered by a local mobility
   anchor.

3.1.  Access Network Identifier Sub-Option

   The Access Network Identifier Sub-Option is used for carrying
   information elements related to the access network to which the
   mobile node is attached.  The format of the Access Network Identifier
   Sub-option is defined as follows.


    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |    ANI Type   | ANI Length    |         Option Data           ~
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


              Figure 3: Access Network Identifier Sub-Option

   ANI Type:  8-bit unsigned integer indicating the type of the Access
      Network Identifier sub-option.  This specification defines the
      following types:

      1 -  Network-Identifier Sub-option

      2 -  Geo-Location Sub-option

      3 -  Operator-Identifier Sub-option

   ANI Length:  8-bit unsigned integer indicating the number of octets
      needed to encode the Network Identifier sub-option excluding the
      ANI Type and ANI Length fields of the sub-option.

3.2.  Network-Identifier Sub-Option

   The Network-Identifier is a mobility sub-option that can be carried
   in Access Network Identifier option defined in Section 3.  This sub-
   option can be used for carrying the IEEE 802.11 SSID name of the
   network to which the mobile node is attached.  There can only be a
   single instance of this specific sub-option in any Access Network
   Identifier option.  The format of this option is defined below.









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    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | ANI Type=1    |  ANI Length   |             SSID              ~
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


                  Figure 4: Network-Identifier Sub-option

   ANI Type:  It should be set to value of (1), indicating that its a
      Network-Identifier sub-option

   ANI Length:  Total length of this sub option, excluding the ANI Type
      and ANI length fields.  The value can be in the range of 2 to 32
      octets.

   SSID:  SSID of the access network to which the mobile node is
      attached.  The string is carried in UTF-8 representation.

3.3.  Geo-Location ANI Sub-Option

   The Geo-Location is a mobility sub-option that can be carried in
   Access Network Identifier option defined in Section 3.  This sub-
   option can be used for carrying the Geo-location of the network to
   which the mobile node is attached.  There can only be a single
   instance of this specific sub-option in any Access Network Identifier
   option.  The format of this option is defined below.


    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  ANI Type=2   | ANI Length=8  |N|     Latitude Degrees        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  La-Minutes   | La-Seconds    |E|     Longitude Degrees       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Lo-Minutes   | Lo-Seconds    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


                   Figure 5: Geo-Location ANI sub-option

   ANI Type:  It should be set to value of (2), indicating that its Geo-
      Location sub-option







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   ANI Length:  Total length of this sub-option, excluding the ANI Type
      and ANI length fields.  It should be set to a value of (8).

   N: When the flag (N) is set to a value of (1), it means North, else
      its South

   Latitude Degrees:  Allowed range from 0 to 90 degrees, northern or
      southern hemisphere as qualified by the (N) flag

   La-Minutes:  Allowed range is 0 to 59.

   La-Seconds:  Allowed range is 0 to 59.  Any fractional values must be
      rounded off to the nearest integer.

   E: When the flag (E) is set to a value of (1), it means East, else
      its West

   Longitude Degrees:  Allowed range from 0 to 90 degrees, eastern or
      western hemisphere as qualified by the (E) flag

   Lo-Minutes:  Allowed range is 0 to 59.

   Lo-Seconds:  Allowed range is 0 to 59.  Any fractional values must be
      rounded off to the nearest integer.

3.4.  Operator-Identifier Sub-Option

   The Operator-Identifier sub-option can be used for carrying the
   operator identifier of the access network to which the mobile node is
   attached.  There can only be a single instance of this specific sub-
   option in any Access Network Identifier option.  The format of this
   option is defined below.


    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | ANI Type=3    |    ANI Length   |   Op-ID Type  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                        Operator Identifier                    ~
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+



                 Figure 6: Operator-Identifier Sub-option






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   ANI Type:  It should be set to value of (3), indicating that its
      Operator-Identifier sub-option

   ANI Length:  Total length of this sub option, excluding the ANI Type
      and ANI length fields.

   Operator Identifier (Op-ID) Type:  8-bit unsigned integer indicating
      the type of the Operator Identifier.  Currently the following
      types are defined:

      0 -  reserved.

      1 -  Vendor ID as a four octet Private Enterprise Number [SMI].

      2 -  Realm of the operator.  Realm names are required to be
         unique, and are piggybacked on the administration of the DNS
         namespace.  Realms are encoded using a domain name encoding
         defined in [RFC1035].

   Operator Identifier:  Up to 253 octets of the operator identifier.
      The encoding of the identifier depends on the used Operator-ID
      Type.  Numeric values are encoded in network byte order and
      strings have no terminating '\0' mark.


4.  Protocol Considerations

   The following considerations apply to the local mobility anchor and
   the mobile access gateway.

4.1.  Mobile Access Gateway Considerations

   o  The conceptual Binding Update List entry data structure maintained
      by the mobile access gateway, described in Section 6.1 of
      [RFC5213], MUST be extended to store the access network
      information associated with the current session.  Specifically,
      the following parameters must be defined.

      Network-Identifier

      Operator-Identifier

      Geo-Location

   o  If the mobile access gateway is configured to support to Access
      Network Information option, it SHOULD include this option in all
      Proxy Binding Update message that it sends to the local mobility
      anchor.  The Access Network Information option SHOULD be



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      constructed as specified in Section 3.  It should include the
      relevant ANI sub-options that the mobile access gateway is
      configured to carry them in the Proxy Mobile IPv6 signaling
      messages.

   o  If the protocol configuration variable,
      EnableANISubOptNetworkIdentifier, is set to a value of (1), the
      mobile access gateway SHOULD include the Network-Identifier sub-
      option.  For including the Network-Identifier sub-option, the
      mobile access gateway needs to be aware of the SSID of the
      Wireless LAN network to which the mobile node is attached.  This
      information may be statically configured on the mobile access
      gateway on a per-interface basis (Example: Access Point (AP-1) is
      attached through interface-1, and the SSID is X).  In some
      deployments, this information can also be dynamically obtained,
      such as through DHCP Option 82, which is the DHCP Relay Agent
      Information option [RFC3046].  When the mobile node sends a DHCP
      Request, the Access Points typically add the SSID information to
      the Option 82 of the DHCP request and when the mobile access
      gateway receives this request, it can parse the Option 82 of the
      DHCP request and obtain the SSID name.

   o  If the protocol configuration variable,
      EnableANISubOptGeoLocation, is set to a value of (1), the mobile
      access gateway SHOULD include the Geo-Location sub-option.  For
      including the Geo-Location sub-option, the mobile access gateway
      needs to be aware of the GPS coordinates of the access point to
      which the mobile node is attached.  This information is typically
      statically configured on that mobile access gateway.  This sub-
      option MUST be constructed as described in Section 3.3.

   o  If the protocol configuration variable,
      EnableANISubOptOperatorIdentifier, is set to a value of (1), the
      mobile access gateway SHOULD include the Operator-Identifier sub-
      option.  For including the Operator-Identifier sub-option, the
      mobile access gateway needs to be aware of the operator identity
      of that access network.  This information is typically statically
      configured on that mobile access gateway.  This sub-option MUST be
      constructed as described in Section 3.4.

   If the mobile access gateway had any of the Access Network
   Information mobility option included the PBU sent to a local mobility
   anchor, then the PBA received from the local mobility anchor is also
   expected to contain the Access Network Information mobility option.
   If the mobile access gateway receives a PBA with a successful Status
   Value but without an Access Network Information mobility option, then
   the mobile access gateway SHOULD log the event and based on its local
   policy MAY proceed to terminate the mobility session.  In this case



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   the mobile access gateway knows the local mobility anchor does not
   understand the Access Network Information mobility option and
   therefore MAY consider it as a misconfiguration of the Proxy Mobile
   IPv6 domain.

4.2.  Local Mobility Anchor Considerations

   o  The conceptual Binding Cache entry data structure maintained by
      the local mobility anchor, described in Section 5.1 of [RFC5213],
      MUST be extended to store the access network information
      associated with the current session.  Specifically, the following
      parameters must be defined.

      Network-Identifier

      Operator-Identifier

      Geo-Location

   o  On receiving a Proxy Binding Update message [RFC5213] from a
      mobile access gateway with the Access Network Information option,
      the local mobility anchor must process the option and update the
      corresponding fields in the Binding Cache entry.

   o  If the received Proxy Binding Update message does not include the
      Access Network Information option, but the mobility session
      associated to that request has the previously notified access
      network specific information elements, the same MUST be updated
      and those information elements previously received MUST be
      removed.

   o  The local mobility anchor MAY choose to use the access network
      information options for applying any access operator specific
      handling or policing of the mobile node traffic.


5.  IANA Considerations

   This document requires the following IANA actions.

      Action-1: This specification defines a new Mobility Header option,
      the Access Network Identifier.  This mobility option is described
      in Section 3.  The Type value for this option needs to be assigned
      from the same numbering space as allocated for the other mobility
      options, as defined in [RFC6275].

      Action-2: This specification defines a new mobility sub-option
      format, Access Network Information (ANI) sub-option.  The format



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      of this mobility sub-option is described in Section 3.1.  This
      sub-option can be carried in Access Network Information option.
      The type value for this sub-option needs to be managed by IANA,
      under the Registry, Access Network Information sub-option.  This
      specification reserves the type values of (1), (2) and (3).
      Approval of new Access Network Information (ANI) sub-option type
      values are to be made through IANA Expert Review.

      Action-3: This specification defines a new mobility sub-option,
      Operator-Identifier sub-option.  The format of this mobility sub-
      option is described in Section 3.4.  The Operator Identifier
      (Op-Id) Type field of this sub-option introduces a new number
      space.  This number space needs to be managed by IANA, under the
      Registry, Operator Identifier Type Registry.  This specification
      reserves the type values of (0), (1) and (2).  Approval of new
      Operator Identifier Type values are to be made through IANA Expert
      Review.


6.  Protocol Configuration Variables

   This specification defines the following configuration variables that
   control the use of Access Network Information related sub-options in
   Proxy Mobile IPv6 signaling messages.  The mobility entities, local
   mobility anchor and the mobile access gateway MUST allow these
   variables to be configured by the system management.  The configured
   values for these protocol variables MUST survive server reboots and
   service restarts.

   EnableANISubOptNetworkIdentifier

      This flag indicates whether or not support for Network-Identifier
      sub-option should be enabled.  This configuration variable is
      available at both in the mobile access gateway and at the local
      mobility anchor.  The default value for this flag is set to (0),
      indicating that the support for Network-Identifier sub-option is
      disabled.  When this flag is set to a value of (1), the mobile
      access gateway SHOULD include this sub-option in the Proxy Binding
      Update messages that it sends to the local mobility anchor.
      Similarly, when this flag is set to a value of (1), the local
      mobility anchor SHOULD enable support for this information
      element.

   EnableANISubOptGeoLocation

      This flag indicates whether or not support for Geo-Location sub-
      option should be enabled.  This configuration variable is
      available at both in the mobile access gateway and at the local



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      mobility anchor.  The default value for this flag is set to (0),
      indicating that the support for Geo-Location sub-option is
      disabled.  When this flag is set to a value of (1), the mobile
      access gateway SHOULD include this sub-option in the Proxy Binding
      Update messages that it sends to the local mobility anchor.
      Similarly, when this flag is set to a value of (1), the local
      mobility anchor SHOULD enable support for this information
      element.

   EnableANISubOptOperatorIdentifier

      This flag indicates whether or not support for Operator-Identifier
      sub-option should be enabled.  This configuration variable is
      available at both in the mobile access gateway and at the local
      mobility anchor.  The default value for this flag is set to (0),
      indicating that the support for Operator-Identifier sub-option is
      disabled.  When this flag is set to a value of (1), the mobile
      access gateway SHOULD include this sub-option in the Proxy Binding
      Update messages that it sends to the local mobility anchor.
      Similarly, when this flag is set to a value of (1), the local
      mobility anchor SHOULD enable support for this information
      element.


7.  Security Considerations

   The Access Network Information option defined in this specification
   is for use in Proxy Binding Update and Proxy Binding Acknowledgement
   messages.  This option is carried like any other mobility header
   option as specified in [RFC6275] and does not require any special
   security considerations.

   The Geo-location sub-option carried in the Access Network Information
   option exposes the geo-location of the mobile node as presented by
   the mobile access gateway and this information should be considered
   as very sensitive.  Care must be taken to secure the Proxy Mobile
   IPv6 signaling messages when carrying this sub-option.  The base
   Proxy Mobile IPv6 specification [RFC6275] specifies the use of IPsec
   for securing the signaling messages and those mechanisms can be
   enabled for protecting this information.


8.  Acknowledgements

   The authors would also like to acknowledge all the discussions
   related to carrying Access Network Information option in Proxy Mobile
   IPv6 protocol signaling.  Additionally, the authors would like to
   thank Carlos Bernardos, Stefano Faccin, Ryuji Wakikawa, Basavaraj



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   Patil, Gerardo Gieratta, and Eric Voit for all the discussions around
   this topic.


9.  References

9.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC5213]  Gundavelli, S., Leung, K., Devarapalli, V., Chowdhury, K.,
              and B. Patil, "Proxy Mobile IPv6", RFC 5213, August 2008.

   [RFC5844]  Wakikawa, R. and S. Gundavelli, "IPv4 Support for Proxy
              Mobile IPv6", RFC 5844, May 2010.

9.2.  Informative References

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

   [RFC3046]  Patrick, M., "DHCP Relay Agent Information Option",
              RFC 3046, January 2001.

   [RFC6275]  Perkins, C., Johnson, D., and J. Arkko, "Mobility Support
              in IPv6", RFC 6275, July 2011.

   [SMI]      IANA, "PRIVATE ENTERPRISE NUMBERS", SMI Network Management
              Private Enterprise Codes, February 2011.

   [TS23203]  3GPP, "Policy and Charging Control Architecture", 2010.

   [TS23402]  3GPP, "Architecture enhancements for non-3GPP accesses",
              2010.


Authors' Addresses

   Sri Gundavelli
   Cisco
   170 West Tasman Drive
   San Jose, CA  95134
   USA

   Email: sgundave@cisco.com





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   Jouni Korhonen
   Nokia Siemens Networks
   Linnoitustie 6
   Espoo  FIN-02600
   Finland

   Email: jouni.nospam@gmail.com


   Mark Grayson
   Cisco
   11 New Square Park
   Bedfont Lakes, FELTHAM  TW14 8HA
   ENGLAND

   Email: mgrayson@cisco.com


   Kent Leung
   Cisco
   170 West Tasman Drive
   San Jose, CA  95134
   USA

   Email: kleung@cisco.com


   Rajesh Pazhyannur
   Cisco
   170 West Tasman Drive
   San Jose, CA  95134
   USA

   Email: rpazhyan@cisco.com

















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