Sunset4 Charter
charter-ietf-sunset4-01-00

Global IPv4 addresses, once freely available, are an increasingly
scarce resource for many who wish to connect to the Internet
today. IPv6 provides an abundance of freely available addresses,
and while deployment alongside IPv4 has begun in earnest, much work
remains.

In order to fully transition the Internet to IPv6, individual
applications, hosts, and networks that have enabled IPv6 must also
be able to operate fully in the absence of IPv4. The Working Group
will point out specific areas of concern, provide recommendations,
and standardize protocols that facilitate the graceful "sunsetting"
of the IPv4 Internet in areas where IPv6 has been deployed. This
includes the act of shutting down IPv4 itself, as well as the
ability of IPv6-only portions of the Internet to continue to
connect with portions of the Internet that remain IPv4-only.

While this work obviously spans multiple IETF areas including
Internet, Operations, Transport, Applications, and Routing, this
working group provides a single venue for the consideration of IPv4
sunsetting. Work in this group shall never impede the deployment of
IPv6, will not duplicate functions and capabilities already
available in existing technologies, and should demonstrate
widespread operational need. Cross- area coordination and support
is essential.

Disabling IPv4 in applications, hosts, and networks is new
territory for much of the Internet today, and it is expected that
problems will be uncovered including those related to basic IPv4
functionality, interoperability, as well as potential security
concerns. The working group will report on common issues, provide
recommendations, and, when necessary, protocol extensions in order
to facilitate disabling IPv4 in networks where IPv6 has been
deployed.

As a rule, deployment scenarios considered by the working group
shall include IPv6-only nodes and networks. Work on technologies
that involve increased sharing of global IPv4 addresses should be
limited to what is necessary for communicating with endpoints or
over networks that are IPv6-only.

The initial work items are:

• NAT64 port allocation and address sharing methods involving
  scenarios where an IPv6-only node is present (and NAT44, as it
  overlaps NAT64 address sharing and port use).

• Gap analysis of IPv4/IPv6 features to facilitate IPv4 sunsetting

• Provisioning methods to signal a dual-stack host to disable or
  depreference the use of IPv4

Goals and Milestones:

Mar 2013 - Submit gap analysis on IPv4 sunsetting to IESG for
consideration as an Informational RFC

Jun 2013 - Submit NAT64 port allocation and address sharing methods
to IESG for consideration as an Informational RFC

Sep 2013 - Submit provisioning methods to signal a dual-stack host
to disable the use of IPv4 to IESG for consideration as
Proposed Standard