IVOA Messaging - the state of the disunion?

[John Taylor]

I thought I'd try to see where we have broad agreement, and where we  
differ.  If I'm wrong, I know I can count on you to correct me.

Areas where we seem to agree
========================
We will concentrate on app2app messaging for a single user on a  
single machine
We will have a hub/daemon process to facilitate the messaging (there  
is actually still some disagreement on this: http://www.ivoa.net/ 
twiki/bin/view/IVOA/ApplicationsMessagingInitialQuestionsFourteen)
The messaging system will be kept simple: no encryption, no  
transactions, guaranteed delivery etc
The messaging protocol will be defined independently of any  
underlying wire protocol


Areas where I think we agree, but I'm not sure
===================================

Applications are free to spawn an instance of the hub/daemon, but  
should behave "nicely" (TBD) if they shut it down.
We won't attempt any clever hand-over from one hub/daemon instance to  
another
Applications will be located dynamically (probably through the hub/ 
daemon) rather than from a remote registry



Areas still to be decided or discussed
=============================

How we bootstrap the connection to the Hub/daemon
Which wire protocol(s) to use
Everything to do with the messages themselves
What we should aim to achieve by May