Mobility for IPv6 (mip6)
(concluded WG)

Description of Working Group

Mobile IPv6 (MIPv6) specifies routing support to permit an IPv6 host to
continue using its "permanent" home address as it moves around
the Internet. Mobile IPv6 supports transparency above the IP
layer, including maintenance of active TCP connections and UDP port
bindings. The specifications for these mechanisms consist of:

draft-ietf-mobileip-ipv6-24 (RFC XXX) and
draft-ietf-mobileip-mipv6-ha-ipsec-06 (RFC XXX)

The protocol as specified in the above two documents can be considered
as the baseline or minimum protocol set for implementing IPv6
mobility. During the development phase of the base protocol, a few
additional features were identified as necessary to facilitate
deployment (described below).

The primary goal of the MIP6 working group will be to enhance base
IPv6 mobility by continuing work on developments that are required for
wide-scale deployments. Additionally the working group will ensure
that any issues identified by the interop testing of the MIPv6
specifications are addressed quickly. Specific work items with this
goal in mind are listed below:

1) Create and maintain an issue list that is generated on the basis of
interop testing and address these issues as enhancements to the
base protocol

2) Features such as renumbering of the home link, home agent discovery,
Route Optimization, which are currently a part of the base
specification can be specified more explicitly as separate
specifications. This will also enable modularizing the Mobile
IPv6 specification further into the minimal subset and add-on
features. Some of these specifications will be identified as
base mechanisms of Mobile IPv6.

3) A number of enhancements to basic IPv6 mobility were identified
during the development of the base specification. These
enhancements will be taken up in a phased manner depending on the
priority identified with each. Below are listed the work items to
be taken up by the WG:

- A bootstrap mechanism for setting up security associations
between the Mobile Node (MN) and Home Agent (HA) that would
enable easier deployment of Mobile IPv6. This bootstrap
mechanism is intended to be used when the device is turned on
the very first time and activates MIPv6. The WG should
investigate and define the scope before solving the problem.

- Improving home agent reliability: in the event of a home agent
crashing, this would allow another home agent to continue
providing service to a given mobile node.

- Support for a Mobile Node changing its home address, either
because of renumbering in its home network or because it
periodically changes addresses (perhaps via RFC3041)

- Route optimization will require security mechanisms for
trusting and updating the binding information.Return-routability
is the basic mechanism for route-optimization. Mechanisms using
a shared secret Key/Security Association will be considered.
Methods for establishing a security association between the
mobile node and the correspondent node are out of the scope
of the WG.

- The working group will also document problem statements
associated with deploying Mobile IPv6 in the following areas:
a. Mobile IPv6 issues in the presence of firewalls
b. Mobile IPv6 deployment and transition issues in the
presence of IPv4/IPv6 networks
c. Multicast issues

It should be noted that there are potential optimizations that might
make mobile IP more attractive for use by certain applications (e.g.,
making handovers "faster"). The latter category of optimizations is
explicitly out-of-scope at this time; this WG will focus on issues
for which there is strong consensus that the work is needed to get
basic mobility deployable on a large scale.

Goals and Milestones