2.3.15 Mobility for IPv4 (mip4)

NOTE: This charter is a snapshot of the 72nd IETF Meeting in Dublin, Ireland. It may now be out-of-date.
In addition to this official charter maintained by the IETF Secretariat, there is additional information about this working group on the Web at:

       Additional MIP4 Web Page

Last Modified: 2008-02-14


Henrik Levkowetz <henrik@levkowetz.com>
Pete McCann <mccap@petoni.org>

Internet Area Director(s):

Jari Arkko <jari.arkko@piuha.net>
Mark Townsley <townsley@cisco.com>

Internet Area Advisor:

Jari Arkko <jari.arkko@piuha.net>

Mailing Lists:

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Archive: http://www.ietf.org/mail-archive/web/mip4/index.html

Description of Working Group:

IP mobility support for IPv4 nodes (hosts and routers) is specified in
RFC3344. RFC 3344 mobility allows a node to continue using its
"permanent" home address as it moves around the Internet. The Mobile
IP protocols support transparency above the IP layer, including
maintenance of active TCP connections and UDP port bindings. Besides
the basic Mobile IPv4 (MIPv4) protocols, several other drafts deal
with concerns such as optimization, security, extensions, AAA support,
and deployment issues.

MIPv4 is currently being deployed on a wide basis (e.g., in cdma2000
networks). The scope of the deployment is on a fairly large scale and
accordingly, the MIP4 WG will focus on deployment issues and on
addressing known deficiencies and shortcomings in the protocol that
have come up as a result of deployment experience. Specifically, the
working group will complete the work items to facilitate interactions
with AAA environments, interactions with enterprise environments when
MIPv4 is used therein, and updating existing protocol specifications
in accordance with deployment needs and advancing those protocols that
are on the standards track.

Work expected to be done by the MIP4 WG as proposed by this charter is
as follows:

1. MIPv4 has been a proposed standard for several years. It has been
adopted by other standard development organizations and has been
deployed commercially. One of the next steps for the WG is to advance
the protocol to draft standard status. As part of advancing base
Mobile IP specs to DS, the MIPv4 NAI RFC (2794) will be revised to
reflect implementation experience.

2. Work items that are pending from the previous Mobile IP WG, which
will be completed by the MIP4 WG, are:

- completion of the MIB for the revised base Mobile IP specification

- regional registration draft.

3. The MIP4 WG will also complete the work on MIPv4 interactions in
VPN scenarios. This work will involve identifying the requirements and
a solution development for MIPv4 operation in the presence of IPsec

4. Additionally, a proposal has been made for how MOBIKE could work
together with MIPv4. This proposal does not describe any new protocol,
but formulates a best current practice for deploying MOBIKE together
with MIPv4. The working group will adopt and complete this document.

5. Some issues have been raised with respect to RFC3519. These will be
identified and addressed as appropriate, through errata, revision of
RFC 3519, and/or supplemental documents as needed.

6. It has been proposed that the FMIP protocol, which has been
standardised for MIPv6 in the MIPSHOP working group, should also be
published as an experimental protocol for MIPv4. A draft for this
exists. The working group will take up and carry this work forward to

7. An extension to carry generic strings in the Registration Reply
message has been proposed. The purpose is to supply supplemental
human-readable information intended to the MN user. The working group
will complete the specification and applicability statement of such an

8. RADIUS attributes for MIP4. A set of RADIUS attributes has been
proposed for MIPv4.

The working group will first produce a requirements specification,
describing how the work differs from the requirements in RFC 2977 and
the functionality provided by RFC 4004 (the MIPv4 Diameter App). The
reason why this first step is required is that RFC 3127 shows that
full RFC 2977 functionality can't be provided by even a considerably
extended RADIUS, so we need to match the requirements to what can be
done within RADIUS.

Provided the requirements work finds approval with ADs and RADEXT WG,
the workgroup will complete the specification of MIPv4 RADIUS
attributes, solicit feedback from the RADEXT WG, adjust, and submit
this for publication. Note that the work may require extensions to the
RADIUS attribute space which will be handled outside the MIP4 WG.

9. MIPv4 Extension for Configuration Options.

Several drafts have proposed extensions to help improve configuration
of MIPv4 clients. The latest proposal is for a general configuration
option extension which could carry information such as e.g., DNS
address and DHCP server address. The working group will take on and
complete one proposal for a configuration option extension.

10. Dual-stack Support

There have been several proposals for how to enable an IPv6 connection
over a network that supports Mobile IPv4. A protocol enhancement to
MIPv4 would allow for IPv6 support in a region where Mobile IPv4 has
already been implemented and deployed. This would allow a dual stack
mobile node to maintain IPv6 connectivity when using MIPv4. The
solution would therefore be applicable only to networks that are
not deploying Mobile IPv6.

The working group will take on and complete one proposal for IPv6 over
Mobile IPv4. This work is restricted to a small protocol extension
similar to current Mobile IPv4 functionality. Support for advanced
Mobile IPv6 functionality is strictly outside the scope.

A problem statement covering both Mobile IPv4 and IPv6 dual-stack
issues is expected to come out of MIP6 WG, and will not be developed
in MIP4 WG.

11. MIPv4 Moving Network Support

The Network Mobility (nemo) working group deals with the problem of
mobility of a whole network, such as might exist inside a vehicle,
train, or airplane. The nemo working group has developed draft
specifications for both IPv6 and IPv4 mobile networks. However, it has
been recognized that the IPv4 version of the protocol can be viewed as
an extension of the basic Mobile IPv4 protocol, and there is good
to do this extension in the mip4 working group. The working group will
take on the MIPv4 network mobility internet draft and progress it along
the standards track. In addition, the working group will take up
extensions to the basic MIPv4 moving network support in the areas of
dynamic prefix assignment and foreign agent support.

12. Asynchronous Notification Mechanism

In some situations, there is a need for Mobile IPv4 entities, such
as the home agent, foreign agent and mobile node to send and
receive asynchronous notification events related to the operation
of the MIPv4 protocol. A couple of examples of such events are
registration revocation from a home agent to a foreign agent in
order to terminate the service (to release resources and end
charging), and notification of pending HA shutdown and indication
of alternative serving HA, from a HA to the mobile node.

The base Mobile IP Specification [RFC3344] does not have a
provision for this. A new MIPv4 message pair which would support
asynchronous notifications, and a notification model describing
how to use these messages has been proposed. The working group
will take on the existing MIPv4 notification message draft as a
starting point, review and update it as needed, and progress it as
a standards track document. In addition, the working group will
also consider defining specific usages of the notification message
based on the examples in the current document.

Goals and Milestones:

Done  AAA Keys for MIPv4 to IESG
Done  MIPv4 VPN interaction problem statement to IESG
Done  Low latency handover to experimental
Done  Experimental MIPv4 message and extensions draft to IESG
Done  Dynamic Home Agent assignment protocol solution to IESG
Done  Revised MIPv4 Challenge/Response (3012bis) to IESG
Done  Regional registration document to IESG
Done  Generic Strings for MIPv4 (Proposed Std.) to the IESG
Done  MIPv4 Mobike interaction (BCP) to the IESG
Done  MIPv4 RADIUS Extensions Requirements to the IESG
Done  MIPv4 Extension for Config. Options (Proposed Std.) to the IESG
Done  FMIPv4 (Experimental) to the IESG
Done  MIPv4 VPN interaction (BCP) to the IESG
Done  Base MIPv4 Mobile Network Support (Draft Std.) to IESG
Feb 2008  Revised MIPv4 specification to IESG for Draft Std.
Mar 2008  Dual-stack MIPv4 (Draft Std.) to IESG
Mar 2008  Revised MIB for MIPv4 (Proposed Std.) to IESG
May 2008  RADIUS Extensions for MIPv4 to the RADEXT WG for comment
May 2008  Notification Mechanism (Draft Std.) to IESG
Jun 2008  RADIUS Extensions for MIPv4 (Proposed Std.) to the IESG
Jul 2008  Revised rfc2794bis (NAI extension) (Draft Std.) to the IESG
Aug 2008  MIPv4 Mobile Network Support for FAs (Draft Std.) to IESG
Aug 2008  MIPv4 Mobile Network Support Dynamic Address Assignment (Draft Std.) to IESG


  • draft-ietf-mip4-rfc2006bis-04.txt
  • draft-ietf-mip4-rfc3344bis-06.txt
  • draft-ietf-mip4-vpn-problem-solution-05.txt
  • draft-ietf-mip4-mobike-connectivity-03.txt
  • draft-ietf-mip4-dsmipv4-06.txt
  • draft-ietf-mip4-nemo-v4-base-11.txt
  • draft-ietf-mip4-generic-notification-message-04.txt
  • draft-ietf-mip4-nemov4-dynamic-01.txt
  • draft-ietf-mip4-nemov4-fa-02.txt

    Request For Comments:

    RFC3846 Standard Mobile IPv4 Extension for AAA Network Access Identifiers
    RFC3957 Standard Authentication, Authorization, and Accounting (AAA) Registration Keys for Mobile IPv4
    RFC4064 Standard Experimental Message, Extension and Error Codes for Mobile IPv4
    RFC4093 I Problem Statement: Mobile IPv4 Traversal of Virtual Private Network (VPN) Gateways
    RFC4433 PS Mobile IPv4 Dynamic Home Agent Assignment
    RFC4636 PS Foreign Agent Error Extension for Mobile IPv4
    RFC4721 PS Mobile IPv4 Challenge/Response Extensions (Revised)
    RFC4857 E Mobile IPv4 Regional Registration
    RFC4881 E Low-Latency Handoffs in Mobile IPv4
    RFC4917 PS Mobile IPv4 Message String Extension
    RFC4988 E Mobile IPv4 Fast Handovers
    RFC5030 I Mobile IPv4 RADIUS requirements

    Meeting Minutes


    0. Note Well
    3. MN Configuration using DHCP
    4. Generic Notification Message -- update
    5. Better-than-nothing FMIPv4