ISSUE: getHubID/getSelfID

[Mark Taylor]

Clients require the public IDs of other subscribed clients so that they 
can target messages to particular recipients.  It can get these using
the hub getRegisteredClients() and getSubscribedClients() calls.

However there are two special client-ids which the registered client might
want to know:

    - its own client ID
    - the ID of the hub (in its capacity as a registered application,
      which is how it would send housekeeping messages like
      "the hub is about to shut down")

It's not obvious why a client would need to know these (e.g. you'd
only need to know your own client-id if you needed to send a message 
to yourself) - but people may come up with reasons (diagnostics and
testing is one possibility).

Currently the hub ID is available from the hub getHubID() method.
Is this method necessary?  There has been the suggestion to remove it
and dictate that the hub public ID must have a fixed well-knowne value
such as "0".

Currently there is no easy way for a client to find its own ID.
Should there be a getSelfID() method?  Or should this value be
returned by the register method (note the Standard Profile register()
method currently returns a private key specific to the application,
but this is not in general the same as the public id).

-- 
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/