Patent ID: 7565434

Claim:
A method of canceling setup of a conference between an originating station and a terminating station via a conference server in a scenario where (a) the conference server has received an invitation message from the originating station seeking to set up the conference with at least the terminating station and (b) the conference server then receives a cancellation message from the originating station before setup of a conference leg between the conference server and the terminating station is complete, the method comprising: in response to the cancellation message, (i) completing setup of the conference leg between the conference server and the terminating station and (ii) then sending a teardown message from the conference server to the terminating station to tear down the conference leg between the conference server and the terminating station, wherein, if the conference server has already received an agreement message from the terminating station agreeing to participate in the session, then completing setup of the conference leg between the conference server and the terminating station comprises sending an acknowledgement message from the conference server to the terminating station; and if the conference server has not yet received the agreement message from the terminating station agreeing to participate in the session, then completing setup of the conference leg between the conference server and the terminating station comprises (i) the conference server receiving the agreement message from the terminating station and (ii) sending the acknowledgement message from the conference server to the terminating station.