Using handle to represent temporary contacts valid during session
Submitted by Pekka Pessi
Assigned to Telepathy bugs list
Description
SIP has concept of forking, where a request for a public ID such as sip:pekka.pessi@example.com can be routed to several user-agents. A SIP session can be formed with any of those user-agents, and there might be multiple sessions active with the same public user ID but different user-agent.
The SIP user-agent identifies itself with a contact URI. The contact URI can be public ID, too, known as globally routable user-agent uri (gruu), or it can be private and reachable only through the original session.
The current Contact Handle semantics do not suit handling user-agent contacts. It is a bit like channel-specific handle, meaning that it has Owner (the public identity for human consumption), but it is usable outside the channel, for instance, when sending text MESSAGEs to the particular SIP user-agent with which you have a StreamedMedia channel.