Subject: [MOBILE-IP] A new (but compatible) approach to do Mobile IP in v6

From: Pekka Nikander <[email-masked]>
Date: Tue, 21 Nov 2000 07:18:16 +0200

We have been considering IPv6 mobility in the context of ad hoc
networks and future wireless devices for some time now.  Along
this work, combined with the ongoing discussion about a mobile
host having several interfaces and therefore several COAs, we've
got an idea that seems like a new one, and produced a related I-D,
http://www.ietf.org/internet-drafts/draft-nikander-mobileip-homelessv6-00.txt

The basic idea is to replace the Binding Cache with what we
call a Host Cache.  While a Binding Cache entry contains a
HA->COA mapping, a Host Cache entry is basically a set of
addresses that are known to belong to a single host.  Sockets
are no more associated with single addresses, but with Host
Cache entries.  This allows source and destination addresses
to be selected on individual packet bases, etc.

Yes, we know that some applications will break, including
FTP and probably a number of UDP applications.  However, since
most of these applications would need to be modified in order
to support IPv6 anyway, maybe that problem would not be that big.

A summary of the background thinking leading to this idea
can be found in
http://www.tml.hut.fi/~pnr/publications/nikander_huc2k.pdf,
and a slightly updated version of the I-D is available at
http://www.tml.hut.fi/~pnr/publications/draft-nikander-mobileip-homelessv6-00.txt

We are currently working on a FreeBSD based prototype implementation,
and should have it out by the San Diego meeting.

--Pekka Nikander
  Ericsson Research NomadicLab