DMM WG                                                          P. Seite
Internet-Draft                                                    Orange
Intended status: Standards Track                                A. Yegin
Expires: January 1, March 10, 2018                                         Actility
                                                           S. Gundavelli
                                                           June 30,
                                                       September 6, 2017

                      MAG Multipath Binding Option


   This specification defines extensions to the Proxy Mobile IPv6
   protocol for allowing a mobile access gateway to register more than
   one proxy care-of-address with the local mobility anchor and to
   simultaneously establish multiple IP tunnels with the local mobility
   anchor.  This capability allows the mobile access gateway to utilize
   all the available access networks for routing mobile node's IP

Status of this Memo

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   provisions of BCP 78 and BCP 79.

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   This Internet-Draft will expire on January 1, March 10, 2018.

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   described in the Simplified BSD License.

Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
   2.  Conventions and Terminology  . . . . . . . . . . . . . . . . .  4
     2.1.  Conventions  . . . . . . . . . . . . . . . . . . . . . . .  5
     2.2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . .  5
   3.  Overview . . . . . . . . . . . . . . . . . . . . . . . . . . .  5
     3.1.  Example Call Flow  . . . . . . . . . . . . . . . . . . . .  5
     3.2.  Traffic distribution schemes . . . . . . . . . . . . . . .  6  7
   4.  Protocol Extensions  . . . . . . . . . . . . . . . . . . . . .  7  8
     4.1.  MAG Multipath-Binding Option . . . . . . . . . . . . . . .  7  8
     4.2.  MAG Identifier Option  . . . . . . . . . . . . . . . . . .  9 10
     4.3.  New Status Code for Proxy Binding Acknowledgement  . . . . 10 11
     4.4.  Signaling Considerations . . . . . . . . . . . . . . . . . 11
   5.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 11 12
   6.  Security Considerations  . . . . . . . . . . . . . . . . . . . 11 12
   7.  Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 12 13
   8.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 12 13
     8.1.  Normative References . . . . . . . . . . . . . . . . . . . 12 13
     8.2.  Informative References . . . . . . . . . . . . . . . . . . 13 14
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 13 14

1.  Introduction

   Multihoming support on IP hosts can greatly improve the user
   experience.  With the simultaneoous use of multiple access networks,
   multihoming brings better network connectivity, reliability and
   improved quality of communication.  Following are some of the goals
   and benefits of multihoming support:

   o  Redundancy/Fault-Recovery

   o  Load balancing

   o  Load sharing

   o  Preferences settings

   According to [RFC4908], users of Small-Scale Networks can take
   benefit of multihoming using mobile IP [RFC6275] and Network Mobility
   (NEMO) [RFC3963] architecture in a mobile and fixed networking
   environment.  This document is introducing the concept of multiple
   Care-of Addresses (CoAs) [RFC5648] that have been specified since

   The motivation for this work is to extend Proxy Mobile IPv6 protocol
   with multihoming extensions [RFC4908] for realizing the following

   o  using GRE as mobile tuneling, possibly with its key extension
      [RFC5845] (a possible reason to use GRE is given on Section 3.2).

   o  using UDP encapsulation [RFC5844] in order to support NAT
      traversal in IPv4 networking environment.

   o  Prefix Delegation mechanism [RFC7148].

   o  Using the vendor specific mobility option [RFC5094], for example
      to allow the MAG and LMA to exchange information (e.g.  WAN
      interface QoS metrics) allowing to make appropriate traffic
      steering decision.

   Proxy Mobile IPv6 (PMIPv6) relies on two mobility entities: the
   mobile access gateway (MAG), which acts as the default gateway for
   the end-node and the local mobility anchor (LMA), which acts as the
   topological anchor point.  Point-to-point links are established,
   using IP-in-IP tunnels, between MAG and LMA.  Then, the MAG and LMA
   are distributing traffic over these tunnels.  All PMIPv6 operations
   are performed on behalf of the end-node and its corespondent node, it
   thus makes PMIPv6 well adapted to multihomed architecture as
   considered in [RFC4908].  Taking the LTE and WLAN networking
   environments as an example, the PMIPv6 based multihomed architecture
   is depicted on Figure 1.  Flow-1,2 and 3 are distributed either on
   Tunnel-1 (over LTE) or Tunnel-2 (over WLAN), while Flow-4 is spread
   on both Tunnel-1 and 2.

      |Flow-2              _----_
      | |         CoA-1  _(      )_   Tunnel-1
      | |    .---=======(   LTE    )========\ Flow-1
      | |    |           (_      _)          \Flow-4
      | |    |             '----'             \
      | | +=====+                              \  +=====+    _----_
      | '-|     |                               \ |     |  _(      )_
      '---| MAG |                                 | LMA |-( Internet )--
      .---|     |                                 |     |  (_      _)
      | .-|     |                               / |     |    '----'
      | | +=====+                              /  +=====+
      | |    |             _----_             /
      | |    |    CoA-2  _(      )_ Tunnel-2 /
      | |    .---=======(   WLAN  )========/ Flow-2
      | |                (_     _)           Flow-3
      | |                  '----'            Flow-4

             Figure 1: Multihomed MAG using Proxy Mobile IPv6

   The current version of Proxy Mobile IPv6 does not allow a MAG to
   register more than one proxy Care-of-Adresse to the LMA.  In other
   words, only one MAG/LMA link, i.e.  IP-in-IP tunnel, can be used at
   the same time.  This document overcomes this limitation by defining
   the multiple proxy Care-of Addresses (pCoAs) extension for Proxy
   Mobile IPv6.

2.  Conventions and Terminology
2.1.  Conventions

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   document are to be interpreted as described in RFC 2119 [RFC2119].

2.2.  Terminology

   All mobility related terms used in this document are to be
   interpreted as defined in [RFC5213], [RFC5844] and [RFC7148].
   Additionally, this document uses the following terms:


      IP-within-IP encapsulation [RFC2473], [RFC4213]

3.  Overview

3.1.  Example Call Flow

   Figure 2 is the callflow detailing multi-access support with PMIPv6.
   The MAG in this example scenario is equipped with both WLAN and LTE
   interfaces and is also configured with the multihoming functionality.
   The steps of the callflow are as follows:

   Steps (1) and (2): the MAG attaches to both WLAN and LTE networks;
   the MAG obtains respectively two different proxy care-of-addresses

   Step (3): The MAG sends, over the WLAN access, a Proxy Binding Update
   (PBU) message, with the new MAG Multipath Binding (MMB) and MAG
   Identifier (MAG-NAI) options to the LMA.  The request can be for a
   physical mobile node attached to the MAG, or for a logical mobile
   node configured on the mobile node.  A logical-NAI (MAG-NAI)
   with ALWAYS-ON configuration logical mobile node is ALWAYS-
   ATTACHED mobile node configuration enabled on the MAG.  The mobility
   session that is created (i.e. create a Binding Cache Entry) on the
   LMA is for the logical-NAI.  The LMA and allocates a Home Network
   Prefix (HNP), that shall will be delegated to mobile nodes, to the MAG. marked with multipath support.

   Step (4): the LMA sends back a Proxy Binding Acknowledgement (PBA)
   including the HNP and other session parameters allocated to the MAG. for that
   mobility session.

   Step (5): IP tunnel (IP-in-IP, GRE ...) is created over the WLAN

   Steps (6) to (8): The MAG repeats steps (3) to (5) on the LTE access.
   The MAG includes the HNP, received on step (4) in the PBU.  The LMA
   update its binding cache by creating a new mobility session for this

   Steps (9) and (10): The IP hosts MN_1 and MN_2 are assigned IP
   addresses from the mobile network prefix delegated by the MAG.

   +=====+ +=====+     +=====+      +=====+      +=====+         +=====+
   | MN_1| | MN_2|     | MAG |      | WLAN|      | LTE |         | LMA |
   +=====+ +=====+     +=====+      +=====+      +=====+         +=====+
      |       |           |            |            |               |
      |       |           |            |            |               |
      |       |           | (1) ATTACH |            |               |
      |       |           | <--------> |            |               |
      |       |           | (2) ATTACH              |               |
      |       |           | <---------------------->|               |
      |       |           | (3) PBU (MAG-NAI, MMB) MMB, ...)             |
      |       |           | ------------------------*-------------->|
      |       |           |                                         |
      |       |           |                                   Accept PBU
      |       |           |                               (allocate HNP,
      |       |           |                                  create BCE)
      |       |           | (4) PBA (MAG-NAI, HNP) MMB, ...)             |
      |       |           | <-----------------------*---------------|
      |       |           | (5) TUNNEL INTERFACE CREATION over WLAN |
      |       |           |-============== TUNNEL ==*==============-|
      |       |           |                                         |
      |       |           | (6) PBU (MAG-NAI, HNP, MMB) MMB, ...)             |
      |       |           | -----------*--------------------------->|
      |       |           |                                         |
      |       |           |                                   Accept PBU
      |       |           |                                 (update BCE)
      |       |           | (7) PBA (MAG-NAI, HNP) MMB, ...)             |
      |       |           | <----------*--------------------------- |
      |       |           | (8) TUNNEL INTERFACE CREATION over LTE  |
      |       |           |-===========*== TUNNEL =================-|
      |   (9) ATTACH      |                                         |
      | <---------------> |                                         |
      |       |(10) ATTACH|                                         |
      |       |<--------> |                                         |

       Figure 2: Functional Separation of the Control and User Plane

3.2.  Traffic distribution schemes

   When receiving packets from the MN, MAG has registered multipath binding with the LMA, there
   will be multiple established overlay tunnels between them.  The MAG distributes packets over
   and the LMA can use any one, or more of the available tunnels paths
   for routing the mobile node's IP traffic.  This specification does
   not recommend, or define any specific traffic distribution scheme,
   however it identifies two well-known approaches that have been established. implementations
   can potentially use.  These approaches are, Per-flow and Per-packet
   Traffic distribution can be
   managed either on a per-flow or on a per-packet basis: schemes.

   Per-Flow Traffic Distribution:

   o  Per-flow traffic management:  In this approach the MAG and the LMA associate each of the IP flow (both upstream
      flows (upstream and downstream) is mapped to a given tunnel, corresponding to specific tunnel path.  The
      packets in a given
      WAN interface.  Flow binding extension [RFC6089] is used to
      exchange, and synchronize, IP flow management policies (i.e. rules
      associating traffic selectors [RFC6088] to a tunnel).

   o  Per-packet management: the LMA and are always routed on the MAG distribute packets,
      belonging to a same IP flow, over more than one bindings (i.e. overlay
      tunnel path; they are never split and routed concurrently on more
      than one WAN interface).  Packet distribution can tunnel path.  It is possible a given flow may be done
      either at the transport level, e.g. using MPTCP or at When
      operating at the IP packet level, different packets distribution
      algorithms are possible.  For example, moved
      from one tunnel path to another, but the algorithm may give
      precedence flow is never split.  The
      decision to one bind a given access: IP flow to a specific tunnel path is
      based on traffic distribution policy.  This traffic distribution
      policy is either statically configured on both the MAG overflows and the
      LMA, or dynamically negotiated over Proxy Mobile IPv6 signaling.
      The Flow Binding extension [RFC6089] and Traffic Selectors for
      Flow Bindings [RFC6088] defines the mechanism and the semantics
      for exchanging the traffic from policy between two tunnel peers and the
      primary access, e.g.  WLAN, to
      same mechanism and the second one, only when load on
      primary access reaches mobility options are used here.

   Per-Packet Traffic Distribution:

   o  In this approach, packets belonging a given threshold. IP flow will be split
      and routed across more than one tunnel paths.  The exact approach
      for traffic distribution, or the distribution
      algorithm weights is left to implementer but whatever outside
      the scope of this specification.  In a very simplistic approach,
      assuming the established tunnel paths have symmetric
      characteristics, the algorithm is,
      packets distribution likely introduces packet latency and out-of-
      order delivery.  LMA and MAG shall thus be able to make reordering
      before packets delivery.  Sequence number can be equally distributed on all the
      available tunnel paths.  In a different scenario when the links
      have different speeds, the chosen approach can be used for
      that purpose, for example using GRE with sequence number option
      [RFC5845].  However, more detailed considerations based on reordering
      and IP packet
      weighted distribution scheme (e.g. definition of packets
      distribution algorithm) are out the scope (Ex: n:m ratio).  However, in any of this document.

   Because latency introduced by per-packet can cause injury these
      chosen approaches, implementations have to some
   application, per-flow and per-packet distribution schemes could be
   used in conjunction.  For example, high throughput services (e.g.
   video streaming) may benefit from per-packet distribution scheme,
   while latency sensitive applications (e.g.  VoIP) are not be spread
   over different WAN paths.  IP flow mobility extensions, [RFC6089] to issues
      related to asymmetric link characteristics and
   [RFC6088], can the resulting
      issues such as re-ordering, buffering and the impact to the
      application performance.  Care must be used taken to ensure there is no
      negative impact to provision the MAG with such flow policies. application performance due to the use of
      this approach.

4.  Protocol Extensions

4.1.  MAG Multipath-Binding Option

   The MAG Multipath-Binding option is a new mobility header option
   defined for use with Proxy Binding Update and Proxy Binding
   Acknowledgement messages exchanged between the local mobility anchor
   and the mobile access gateway.

   This mobility header option is used for requesting multipath support.
   It indicates that the mobile access gateway is requesting the local
   mobility anchor to register the current care-of address associated
   with the request as one of the many care-addresses through which the
   mobile access gateway can be reached.  It is also for carrying the
   information related to the access network associated with the care-of

   The MAG Multipath-Binding option has an alignment requirement of
   8n+2.  Its format is as shown in Figure 3:

   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      |    If-ATT     |    If-Label   |
   |  Binding-Id   |B|O|             RESERVED                      |

                  Figure 3: MAG Multipath Binding Option


      <IANA-1> To be assigned by IANA.


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

   Interface Access-Technology Type (If-ATT)

      This 8-bit field identifies the Access-Technology type of the
      interface through which the mobile node is connected.  The
      permitted values for this are from the Access Technology Type
      registry defined in [RFC5213].

   Interface Label (If-Label)
      This 8-bit field unsigned integer represents the interface label.

      The interface label represented as is an
      unsigned integer.  The MAG identifies identifier configured on the label for each WAN
      interface of the MAG.  All the WAN interfaces through which it registers of the MAG that are
      used for sending PBU messages are configured with a pCoA label.  The
      labels merely identify the type of WAN interface and are primarily
      used in Application routing policies.  For example, a Wi-Fi
      interfaces can be configured with a label RED and a LTE interface
      with a label BLUE.  Furthermore, the LMA.  When
      using static traffic flow policies same label may be configured
      on two WAN interfaces of similar characteristics (Ex: Two Ethernet
      interfaces with the mobile node and same label).

      Interfaces labels are signaled from the LMA, MAG to LMA in the label can PBU
      messages and both the LMA and MAG will be able to mark each of the
      dynamically created Binding/Tunnel with the associated label.
      These labels are used for in generating forwarding rules.  For
      example, consistent application routing
      rules on the operator may have policy which binds traffic for
      Application "X" to an interface with Label "Y".  When a
      registration through an interface matching Label "Y" gets
      activated, both the LMA and the mobile node MAG.  For example, there can dynamically generate be
      forwarding policy for forwarding traffic for Application "X"
      through the tunnel matching requiring HTTP packets to be routed over interface that
      has Label "Y".  Both the LMA RED, and if any of the
      mobile node can route RED interfaces are not available,
      the Application-X traffic through that needs to be routed over the BLUE interface.  The permitted values for If-Label are 1 through 255. MAG
      and the LMA will be able to apply this Routing Rule with the
      exchange of Labels in PBU messages and by associating the
      application flows to tunnels with the matching labels.

   Binding-Identifier (BID)

      This 8-bit field unsigned integer is used for carrying the binding identifier.  It
      uniquely identifies a specific binding of identifying the mobile node, to
      which this request can be associated.  Each binding identifier is
      represented as an unsigned integer. binding.
      The permitted values are 1 through 254.  The BID value of values, 0 and 255 are

      The MAG identifies each of the mobile
      access gateway assigns node's binding with a unique value for each of its interfaces
      identifier.  The MAG includes them the identifier in the message. PBU message
      and when the PBU request is accepted by the LMA, the resulting
      Binding is associated with this binding identifier.

   Bulk Re-registration Flag (B)

      This flag, if set to a value of (1), is to notify the local
      mobility anchor to consider this request as a request to update
      the binding lifetime of all the mobile node's bindings, upon
      accepting this specific request.  This flag MUST NOT be set to a
      value of (1), if the value of the Registration Overwrite Flag (O)
      is set to a value of (1).

   Binding Overwrite (O)

      This flag, if set to a value of (1), notifies the local mobility
      anchor that upon accepting this request, it should replace all of
      the mobile node's existing bindings with this binding.  This flag
      MUST NOT be set to a value of (1), if the value of the Bulk Re-
      registration Flag (B) is set to a value of (1).  This flag MUST be
      set to a value of (0), in de-registration requests.


      This field is unused in this specification.  The value MUST be set
      to zero (0) by the sender and MUST be ignored by the receiver.

4.2.  MAG Identifier Option

   The MAG Identifier option is a new mobility header option defined for
   use with Proxy Binding Update and Proxy Binding Acknowledgement
   messages exchanged between the local mobility anchor and the mobile
   access gateway.  This mobility header option is used for conveying
   the MAG's identity.

   This option does not have any alignment requirements.

   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      |  Subtype      |  Reserved     |
   |                           Identifier ...                      ~

                      Figure 4: MAG Identifier Option


      <IANA-2> To be assigned by IANA.


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


      One byte unsigned integer used for identifying the type of the
      Identifier field.  Accepted values for this field are the
      registered type values from the Mobile Node Identifier Option
      Subtypes registry.

      This field is unused in this specification.  The value MUST be set
      to zero (0) by the sender and MUST be ignored by the receiver.


      A variable length identifier of type indicated in the Subtype

4.3.  New Status Code for Proxy Binding Acknowledgement

   This document defines the following new Status Code value for use in
   Proxy Binding Acknowledgement message.

   The LMA SHOULD use this error code when rejecting a Proxy Binding
   Update message from a MAG requesting a multipath binding.  Following
   is the potential reason for rejecting the request:

   o  The LMA does not support multipath binding.

   CANNOT_SUPPORT_MULTIPATH_BINDING (Cannot Support Multipath Binding):

4.4.  Signaling Considerations

   o  The MAG when requesting multipath support MUST include the MAG
      Multipath Binding Option (Section 4.1) in each of the PBU messages
      that it sends through the different WAN interfaces.  The inclusion
      of this option serves as a hint that the MAG is requesting
      Multipath support.  Furthermore, the MAG Identifier option MUST
      also be present in the PBU message.

   o  If the LMA is a legacy LMA that does not support this
      specification, the LMA will skip the MAG Multipath Binding option
      (and MAG NAI option) and process the rest of the message as
      specified in the base Proxy Mobile IPv6 specification ([RFC5213]).
      Furthermore, the LMA will not include the MAG Multipath Binding
      option (or the MAG NAI Option)in the PBA message.  The MAG on
      receiving the PBA message without the MAG Multipath Binding option
      SHOULD disable Multipath support for the mobile node.

   o  If the mobile node is not authorized for Multipath support, then
      the LMA will reject the request by sending a PBA message with the
      Status field value set to CANNOT_SUPPORT_MULTIPATH_BINDING
      (Section 4.3).  The LMA will echo the MAG Multipath Binding option
      and the MAG NAI option in the PBA message.  The MAG on receiving
      this message SHOULD disable Multipath support for the mobile node.

   o  If the request for multipath support is accepted, then the LMA
      SHOULD enable multipath support for the mobile node and SHOULD
      also echo the MAG Multipath Binding option and the MAG NAI option
      in the corresponding PBA message.

5.  IANA Considerations

   This document requires the following IANA actions.

   o  Action-1: This specification defines a new mobility option, the
      MAG Multipath-Binding option.  The format of this option is
      described in Section 4.1.  The type value <IANA-1> for this
      mobility option needs to be allocated from the Mobility Options
      registry at <>.
      RFC Editor: Please replace <IANA-1> in Section 4.1 with the
      assigned value and update this section accordingly.

   o  Action-2: This specification defines a new mobility option, the
      MAG Identifier option.  The format of this option is described in
      Section 4.2.  The type value <IANA-2> for this mobility option
      needs to be allocated from the Mobility Options registry at
      <>.  RFC
      Editor: Please replace <IANA-2> in Section 4.2 with the assigned
      value and update this section accordingly.

   o  Action-3: This document defines a new status value,
      Binding Acknowledgement message, as described in Section 4.3.
      This value is to be assigned from the "Status Codes" registry at
      <>.  The
      allocated value has to be greater than 127.  RFC Editor: Please
      replace <IANA-4> <IANA-3> in Section 4.3 with the assigned value and update
      this section accordingly.

6.  Security Considerations

   This specification allows a mobile access gateway to establish
   multiple Proxy Mobile IPv6 tunnels with a local mobility anchor, by
   registering a care-of address for each of its connected access
   networks.  This essentially allows the mobile node's IP traffic to be
   routed through any of the tunnel paths based on the negotiated flow
   policy.  This new capability has no impact on the protocol security.
   Furthermore, this specification defines two new mobility header
   options, MAG Multipath-Binding option and the MAG Identifier option.
   These options are carried like any other mobility header option as
   specified in [RFC5213].  Therefore, it inherits security guidelines
   from [RFC5213].  Thus, this specification does not weaken the
   security of Proxy Mobile IPv6 Protocol, and does not introduce any
   new security vulnerabilities.

7.  Acknowledgements

   The authors of this draft would like to acknowledge the discussions
   and feedback on this topic from the members of the DMM working group.
   The authors would also like to thank Jouni Korhonen, Jong Hyouk Lee,
   Dirk Von-Hugo, Seil Jeon, Carlos Bernardos and Bernardos, Robert Sparks Sparks, Adam
   Roach, Kathleen Moriarty, Hilarie Orman, Ben Campbell, Warren Kumari,
   Mirja Kuehlewind, for their review feedback.

8.  References

8.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/
              RFC2119, March 1997,

   [RFC3963]  Devarapalli, V., Wakikawa, R., Petrescu, A., and P.
              Thubert, "Network Mobility (NEMO) Basic Support Protocol",
              RFC 3963, DOI 10.17487/RFC3963, January 2005,

   [RFC5094]  Devarapalli, V., Patel, A., and K. Leung, "Mobile IPv6
              Vendor Specific Option", RFC 5094, DOI 10.17487/RFC5094,
              December 2007, <>. <>.

   [RFC5213]  Gundavelli, S., Ed., Leung, K., Devarapalli, V.,
              Chowdhury, K., and B. Patil, "Proxy Mobile IPv6",
              RFC 5213, DOI 10.17487/RFC5213, August 2008,

   [RFC5648]  Wakikawa, R., Ed., Devarapalli, V., Tsirtsis, G., Ernst,
              T., and K. Nagami, "Multiple Care-of Addresses
              Registration", RFC 5648, DOI 10.17487/RFC5648,
              October 2009, <>. <>.

   [RFC5844]  Wakikawa, R. and S. Gundavelli, "IPv4 Support for Proxy
              Mobile IPv6", RFC 5844, DOI 10.17487/RFC5844, May 2010,

   [RFC5845]  Muhanna, A., Khalil, M., Gundavelli, S., and K. Leung,
              "Generic Routing Encapsulation (GRE) Key Option for Proxy
              Mobile IPv6", RFC 5845, DOI 10.17487/RFC5845, June 2010,

   [RFC6088]  Tsirtsis, G., Giarreta, G., Soliman, H., and N. Montavont,
              "Traffic Selectors for Flow Bindings", RFC 6088,
              DOI 10.17487/RFC6088, January 2011,

   [RFC6089]  Tsirtsis, G., Soliman, H., Montavont, N., Giaretta, G.,
              and K. Kuladinithi, "Flow Bindings in Mobile IPv6 and
              Network Mobility (NEMO) Basic Support", RFC 6089,
              DOI 10.17487/RFC6089, January 2011,

   [RFC6275]  Perkins, C., Ed., Johnson, D., and J. Arkko, "Mobility
              Support in IPv6", RFC 6275, DOI 10.17487/RFC6275,
              July 2011, <>. <>.

   [RFC7148]  Zhou, X., Korhonen, J., Williams, C., Gundavelli, S., and
              CJ. Bernardos, "Prefix Delegation Support for Proxy Mobile
              IPv6", RFC 7148, DOI 10.17487/RFC7148, March 2014,

8.2.  Informative References

   [RFC2473]  Conta, A. and S. Deering, "Generic Packet Tunneling in
              IPv6 Specification", RFC 2473, DOI 10.17487/RFC2473,
              December 1998, <>. <>.

   [RFC4213]  Nordmark, E. and R. Gilligan, "Basic Transition Mechanisms
              for IPv6 Hosts and Routers", RFC 4213, DOI 10.17487/
              RFC4213, October 2005,

   [RFC4908]  Nagami, K., Uda, S., Ogashiwa, N., Esaki, H., Wakikawa,
              R., and H. Ohnishi, "Multi-homing for small scale fixed
              network Using Mobile IP and NEMO", RFC 4908, DOI 10.17487/
              RFC4908, June 2007,

Authors' Addresses

   Pierrick Seite
   4, rue du Clos Courtel, BP 91226
   Cesson-Sevigne  35512


   Alper Yegin


   Sri Gundavelli
   170 West Tasman Drive
   San Jose, CA  95134