Basic idea: use a presence notification as an ICE ‘initiate’ message
Essentially requires presentities to gather the same address set they would assemble for SDP
Watchers can begin ICE tests against those addresses
Subsequently display the results of the tests as ‘connectivity status’ of the target
Green/yellow/red (but application-specific)
Lets you know, before you attempt an INVITE, if it is probable that media can be set up
PPT Version