Multi-node network implementation of WSRM

[<ian.c.jones@bt.com>]

Team,

	I raised this on the last call and I have now written something
for us to share:

	The ebXML Messaging Services TC is investigating how to extend
WS-ReliableMessaging functionality across a multi-node network and not
just point-to-point.  We are currently at an early stage and would
welcome any ideas, suggestions and help.  We have identified a number of
scenarios that restrict the level of functionality to an initially
controllable scope, the first 2 are:
1.	The intermediaries are transparent and do not change the ebXML
or WSRM headers/body in anyway - the first issue is establishing the
sequence.
2.	Relayed acknowledgements - each intermediary does not return an
acknowledgement until it has received one - may be resource hungry and
fragile as many connections may be open across a network and compounded
if large messages are exchanged.

There are also general concerns about routing across networks/race
condition/retry etc.
From our initial work it appears that extra functionality either at the
source and destination or the intermediary will be required possibly
including changes to the WSRM handlers to delay acknowledgement
generation for example.

	These are the simplest business requirement driven scenarios and
we have the potential for more complexity but wish to solve something
simple first and try and generalise or expand it to cover more scenarios
and test them as the attempt to define the general case first lead to
too many issues and questions that interplayed and prevented much
progress.

	If anyone has attempted any multi-node network implantations of
WSRM we would really like to know.
 
Thanks all and may the next year be more successful than the past.


Ian Jones
Chair OASIS ebXML Messaging Services TC 
Email: ian.c.jones@bt.com