Subject: Re: [MOBILE-IP] handover

From: "Alan O'Neill" <[email-masked]>
Date: Fri, 28 Apr 2000 08:15:51 -0400

All,

For those who do not know me I work in BT on all IP architecture with primary focus on UMTS Rel2001 but also including mobility
across a range of access technologies. I am also co-author of <draft-oneill-ema-01.txt> which attempts to provide a generic IP
hand-over architecture which will support UMTS:GTP, MobileIP, but mainly routed mobility. Co-authors are Scott Corson the
MANET wg co-chair and George Tsirtsis also of BT.

We would like to to see  hand-over control and interactions with the radio systems to be defined in a
generalised way so that an operator can migrate from existing GTP through possibly MobileIP to the holy grail of a scalable
mobile enhanced routing protocol (we use modified MANET:TORA for this at the moment), with co-existence where commercial
models dictate for the data-path options (tunnelled / routed etc) . The aim is to facilitate a common IP hand-over interface so that
the operator can have all options co-exist, and support evolution between them. We can also see big dangers and interoperability
problems if each affected working group designs it's own, non-interworking  fast IP hand-over solutions and associated interfaces
into the access technologies and systems.

The Edge mobility Architecture draft <draft-oneill-ema-01.txt> avoids many of the details but hopefully the reader can see the
clear need to enable tunnelled and native routed solutions to co-exist,  re-using the same AAA, access signalling and policy
elements, plus the interfaces into many different access technologies and systems. Our view at this stage is that the solution for
the signalling plane requires a combination of extended MobileIP signalling to embrace GTP and routed mobility requirements,
plus DHCP extensions. We are presently preparing drafts which detail the mapping of EMA to UMTS, and  the detailed signalling
pieces.

It seems to make sense that a separate short working group be first formed to define the scope and
architecture for the IP hand-over work so that common pieces can be identified along with the full set of new protocol
requirements. We can then let each existing or resulting working group deal with those protocol requirements which clearly will
include MobileIP. Possibly a BOF could be specifically scheduled at the next IETF or even some sort of interim meeting given
the all-IP timescales we are all experiencing in this space.

Comments appreciated.

Regards
Alan O'Neill, Scott Corson, George Tsirtsis....