[AG-DEV] Bridge Beacons

[Andrew A Rowley]

Hi,

Now that users can use any bridge with AG3, and that distant users will tend to end up using different bridges, we are running into the problem of bridges not being able to speak to each other.  One way forward with this problem is to add a beacon to the bridge implementation, so that it is automatically run when the bridge is run.  This would then show (to some extent) which bridges can speak to each other.  

My idea is to have each bridge send out some traffic to a specified multicast address (this could be included in the registry, or else specified on the command line) and port.  This could simply identify the bridge, or be more complex like the standard multicast beacon.  Each bridge can listen for this from other bridges and keep track of the current visibility of the bridge from their point of view.  Then, the bridges can have web service calls built in that get this data out, so that the client (or another web page) can display a matrix.  

This could then also be extended in the future so that when a client starts using a bridge, an event message is sent to the venue.  If another client decides to use a bridge, the bridge will be chosen from a subset that can currently speak to the one that the first client chose (or even have the client choose the same bridge).

If anyone wants to have a look at this, has comments about this or can see any flaws in this design, please let me know!

Andrew :)

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