SAMP Bridge

[Mark Taylor]

As mentioned in my previous message, JSAMP 1.0 contains a new component
called the Bridge.  It is documented at the following URLs on the JSAMP
site:

   http://software.astrogrid.org/doc/p/jsamp/1.0/bridge.html
   http://software.astrogrid.org/doc/p/jsamp/1.0/commands.html#Bridge

as well as in the javadocs.

What this allows you to do is to connect two (or more) hubs together,
so that clients on one can talk to clients on the other, as if they
were all registered on the same local hub.  The bridge is a normal
SAMP client (or rather a number of SAMP clients - it will register
multiple times with each connected hub), so it can work with any
hub implementations, not just JSAMP's.

This development was largely inspired by Ivan and Igor's entertaining
demonstration at the Strasbourg Interop which some of you might 
remember, though the idea of inter-host messaging has been lurking
in the background since the early days of PLASTIC.
Use of the bridge would make the kind of collaborative working in
that demo (clients running on different machines communicating with 
each other) somewhat easier to set up, and would solve some, though 
not all, of the issues that the simple approach (use one hub and 
point all clients at it) encounters.  It does not solve the problem
of firewalls getting in the way, though it could be a step towards
doing that.

An obvious use of the bridge would be connecting two hubs on two 
different hosts, used by two different people, so they can share
data and control of applications.  Another possibility would be 
connecting client communities which use incompatible SAMP Profiles.
You may be able to think of other similar or maybe quite different 
uses.  

I'm not sure yet whether this is a useful infrastructure component
or just a toy.  I'm interested in other people's opinions on the topic.  
Any further discussion, either privately or on list, is very welcome.

Mark

--
Mark Taylor   Astronomical Programmer   Physics, Bristol University, UK
m.b.taylor at bris.ac.uk +44-117-928-8776 http://www.star.bris.ac.uk/~mbt/