Subject: WG Review: Recharter of Mobility Extensions (netext)

From: IESG Secretary <[email-masked]>
Date: Tue, 19 Jan 2010 12:27:45 -0800 (PST)

A modified charter has been submitted for the Mobility Extensions (netext)
working group in the Internet Area of the IETF.  The IESG has not made any
determination as yet.  The modified charter is provided below for
informational purposes only.  Please send your comments to the IESG
mailing list ([email-masked]) by Tuesday, January 26, 2010.

This update of the NETEXT working group's charter involves adding work
items related to cross-interface handover and flow mobility that were
discussed in the NETEXT2 BOF but not adopted by the IETF. After
discussions in the NETEXT WG meeting in Hiroshima, a significantly
reduced scope for the work was adopted, and this work is now being added
to the charter. In addition, one work item on RADIUS support moves from
the NETLMM WG to this WG. The differences to the current charter can be
seen at
http://www.arkko.com/ietf/netext/recharter_new_jari2-from-old.diff.html

Mobility Extensions (netext)
----------------------------
Last Modified: 2010-01-19

Current Status: Active Working Group

Additional information is available at tools.ietf.org/wg/netext

Chair(s):

* Rajeev Koodli <[email-masked]>
* Basavaraj Patil <[email-masked]>

Internet Area Director(s):

* Ralph Droms <[email-masked]>
* Jari Arkko <[email-masked]>

Internet Area Advisor:

* Jari Arkko <[email-masked]>

Mailing Lists:
General Discussion: [email-masked]
To Subscribe: https://www.ietf.org/mailman/listinfo/netext
Archive: http://www.ietf.org/mail-archive/web/netext/current/maillist.html

Description of Working Group:

Proxy Mobile IPv6, specified in RFC 5213, is a network-based mobility
protocol. It uses a Mobile Access Gateway (MAG) and a Local Mobility
Anchor (LMA) to allow hosts to move around within a domain while keeping
their address or address prefix stable. Proxy Mobile IPv6 has been
incorporated into a number of products and deployments are starting.
Certain deployment considerations, including localized routing and bulk
refresh of lifetime are already emerging.

The working group will focus on the following topics relevant for
network-based mobility:

Localized Routing: a specification for routing traffic between the
MAG(s) without involving the LMA. That is, allow the MAGs to route
traffic between hosts from one MAG to another, without being tunneled
all the way to the LMA. This reduces latency and backhaul load.
Applications such as voice can benefit from the reduced latency.

Bulk Refresh: a specification of improving the signaling load for
binding lifetime refresh. The current specifications call for the
handling of each mobility session independent of each other. When a
large number of hosts are served by a single MAG, a periodic refresh of
the binding lifetimes can lead to a signaling storm. The purpose of the
Bulk Refresh feature is to construct a protocol feature that allows such
refreshes to occur on a per-MAG basis.

LMA Redirection: a specification for allowing an LMA to redirect a MAG
to another LMA. This is primarily needed as a way to perform load
balancing. This functionality is complementary to implementation
techniques that allow distributed MAG implementations to move tasks
around without a visible impact at the protocol level, and the
initial LMA discovery work in the NETLMM WG. An applicability statement
describing the situations where the new functionality is or is not
applicable has to be included in the specification.

Hiding access technology changes from host IP layer: Proxy mobility is
based on the assumption that changes in host IP stacks are
undesirable. However, link layer implementations can hide the
actually used physical interfaces from the IP stack. For instance, a
single interface might transmit packets over different media, as is
common practice in certain radio networks. This can be used to achieve
inter-access handovers or flow mobility, i.e., the movement of
selected flows from one access technology to another. The
specification of any actual link layer mechanisms is outside the scope
of the working group, but the group works on the following:

- Informational applicability statement that analyzes the issues
involved with this approach and characterizes the contexts in which
such use is or is not appropriate.

- The working group will determine if protocol extensions are required
between the Proxy Mobile IPv6 network nodes (MAGs and LMAs) to
support the ability for a single host interface to transmit packets
over different media and the ability to distribute specific traffic
flows on different media components of that single interface. The
relevant protocol extensions will be developed as necessary. The WG
will assume that there the host has an interface that is capable of
employing multiple media.

Radius Extensions to PMIP6: In order to enable network based
mobility using PMIP6, the policy profile needs to signal a set of
attributes and policies to the MAG and LMA. New Radius attributes
need to be specified that are relevant to PMIP6 based
mobility. This work item will specify Radius extensions and
attributes specific to PMIP6.

The work in this charter is entirely internal to the network and does
not affect host IP stack operation in any way (except perhaps through
impacting packet forwarding capacity visible to the hosts). The working
group is not allowed to specify new IP layer protocol mechanisms to signal
mobility related events between the host and the network.

The proposed activity will be complementary to the existing IETF Working
Groups, notably the NETLMM and MEXT WGs. The NETEXT working group will
also act as the primary forum where new extensions on top of the Proxy
Mobile IPv6 protocol can be developed. The addition of such new
extensions to the working group involves addition of the extension to
this charter through the normal rechartering process.

Goals and Milestones:

May 2009 WG chartered
Jul 2009 Initial WG draft on Bulk Refresh
Jul 2009 Decision on the inclusion of possible additional work
items
Sep 2009 Initial WG draft on LMA Redirection
Sep 2009 Initial WG draft on Localized Routing
Dec 2009 Submit Bulk Refresh to IESG for publication as a
Proposed Standard RFC
Jan 2010 Submit LMA Redirection to IESG for publication as a
Proposed Standard RFC
Mar 2010 Initial WG document on RADIUS extensions to PMIP6
Apr 2010 Submit Localized Routing to IESG for publication as a
Proposed Standard RFC
May 2010 Initial WG document on Applicability Statement on
Multiple Media on One Interface
Jun 2010 WG decision on what Proxy Mobile IPv6 support is needed
to support multiple media on one interface
Sep 2010 Initial WG document(s) on Proxy Mobile IPv6 Extensions
to Support Multiple Media on One Interface
Oct 2010 Submit RADIUS extensions to PMIP6 to IESG for
publication as a Proposed Standard
Dec 2010 Submit Applicability Statement on Multiple Media on One
Interface to IESG for publication as Informational RFC
Feb 2011 Submit Proxy Mobile IPv6 Extensions to Support Multiple
Media on One Interface for publication as Proposed Standard RFC(s)