MIPv6 Signaling and Handoff Optimization BOF (mipshop)
Wednesday, July 16 at 0900-1130
================================
CHAIRS: Basavaraj Patil <Basavaraj.Patil@nokia.com>
Gabriel Montenegro <gab@sun.com>
AGENDA:
NOTE: MIPSHOP is in the process of being approved as a working group.
Final approval MAY happen before Vienna IETF. Details,
work items, chairs, etc are likely to change.
1. Charter Discussion: 15 min
I-D: none
Presenters: Chairs
2. DNA interactions: 10 min
I-D: none
Presenter: Greg Daley
The Detecting Network Attachment (DNA) BOF will deal with
issues of how to quickly enable a node to obtain
presence on a new link. Several such optimizations
have been discussed to improve handoff (OptiDAD, aDAD,
etc). These may be further worked on by DNA.
DNA may also deal with movement detection issues that are
useful in the context of fast handoffs. This slot
will allow for discussion on how best to coordinate with
these DNA efforts which are of utmost importance to
MIPSHOP.
3. FMIPv6 Update: 15 min
I-D: draft-ietf-mobileip-fast-mipv6-06.txt
Presenter: Rajeev Koodli
Summary of the latest changes, and specially
time to clarify and discuss the latest exchanges on the
list concerning alternatives around address assignment.
4 HMIPv6 update and lmm-requirements: 15 min
I-D: draft-ietf-mobileip-hmipv6-08.txt
draft-ietf-mobileip-lmm-requirements-03.txt
Presenter: Hesham Soliman
Latest changes to the draft, in particular, the
OCOT (on-link care-of address test) addition.
Also, review of HMIPv6 in the light of lmm-requirements.
5. Implementation reports: 20 min
I-D: none
Presentors: Nokia (Rajeev Koodli), Docomo (James Kempf)
and Monash University (Nick Moore or Greg Daley)
This slot allows implementors to report on their work
with particular attention to lessons learned,
areas found to be troublesome, etc.
Status of WG I-Ds (MIPSHOP related)
draft-ietf-mobileip-hmipv6-08.txt
draft-ietf-mobileip-fast-mipv6-06.txt
draft-ietf-mobileip-lmm-requirements-03.txt
All, work in progress
Charter:
--------
Mobile IPv6 specifies routing support to permit IP hosts using IPv6 to
move between IP subnetworks while maintaining session continuity. Mobile
IPv6 supports transparency above the IP layer, including maintenance of
active TCP connections and UDP port bindings.
To accomplish this, the mobile node notifies its home agent of the
current binding between its home address and its care of address. This
binding allows a mobile node to maintain connectivity with the Internet
as it moves between subnets. However, packets between the mobile node
and a correspondent node incur sub-optimal triangle routing through
the home agent. To avoid this, a mobile node can optionally optimize
routing by performing a binding update with the correspondent node.
Depending on what steps a mobile node must perform on a new subnet, the
lag between when the mobile node has layer 2 connectivity and when it
begins sending and receiving packets on the new link may be substantial. A
mobile node must first detect at layer 3 that its point of attachment has
changed, then it must perform configuration on the new link, including
router discovery and configuring a new care of address. After that,
the mobile node must perform binding updates with the home address and
any correspondent nodes. Any packets between the correspondent node
and the mobile node sent or in-flight during this time arrive at the
old care of address, where they are dropped since the mobile node no
longer has link connectivity with the old subnet. Such packet loss may
have significant adverse effects.
The Mobile IP Working group has been developing two technologies to
address the issues of signaling overhead and handoff latency/packet loss.
These technologies are :
- Hierarchical Mobile IPv6 mobility management (HMIPv6)
This deals with reducing the amount and latency of signaling
between a MN, its Home Agent and one or more correspondents by
introducing the Mobility Anchor Point (MAP) (a special node
located in the network visited by the mobile node). The MAP
acts somewhat like a local home agent for the visiting mobile
node by limiting the amount of signalling required outside the
MAP's domain.
- Fast Handovers for Mobile IPv6 (FMIPv6)
This reduces packet loss by providing fast IP connectivity as
soon as a new link is established. It does so by fixing up the
routing during link configuration and binding update, so that
packets delivered to the old care of address are forwarded to the
new. In addition, FMIPv6 provides support for preconfiguration of
link information (such as the subnet prefix) in the new subnet
while the mobile node is still attached to the old subnet. This
reduces the amount of preconfiguration time in the new subnet.
These technologies can be used separately or together to reduce or
eliminate signaling overhead and packet loss due to handoff delays in
Mobile IPv6.
The MIPSHOP Working Group will use the work begun in the Mobile IP
Working Group on HMIPv6 and FMIPv6 as a basis for continued work in
these technologies.
In addition to the above bases for protocol proposals, the MobileIP
working group developed a set of requirements for "Localized Mobility
Management (LMM)", whereby a Mobile Node is able to continue receiving
packets in a new subnet before the corresponding changes in either the
Home Agent or Correspondent Node binding. The MIPSHOP working group
will further refine these requirements, and subsequently use them to
ensure that they are met by the protocol proposals being developed.
The working group may engage in the following work:
- Selection of a default security protocol to secure binding
updates between the mobile node and the old access router in FMIPv6.
- Refining the scope of Fast Handoff to address only the most
common scenarios
- Applicability of FMIPv6 in the case of 802.11 networks
- Address security for binding updates in HMIPv6
- Definition of a MAP discovery protocol for HMIPv6 that does not
require modification to routers.
Because work ongoing or originating in other working groups may suggest
changes or alternative designs for HMIPv6 and FMIPv6, these specifications
will be advanced as Experimental RFCs until more experience is obtained
with IP mobility in IPv6. This implies that in the future, the working
group may be rechartered to pursue other experimental specifications as
well as standards track specifications.