Patent ID: 8775636

Claim:
A system for switching a click to dial (CTD) service to a multimedia conference service, comprising a console, an application server, at least two user equipment and a media server, wherein: the console is configured to send a first INVITE message to the application server via a Next Generation Network (NGN) to trigger the multimedia conference service if at least one user equipment needs to switch from the CTD service to the multimedia conference service, wherein said first INVITE message carries a command for switching the CTD service to the multimedia conference service and comprises a session description protocol (SDP) of the console, and return a third ACK message to the application server; the application server is configured to receive said first INVITE message, send a re-INVITE message to the at least two user equipment respectively, send a second INVITE message to the media server, wherein said second INVITE message carries the SDP that the application server has received, return a first ACK message to the media server, send a second ACK message to the at least two user equipment respectively at the same time, wherein said second ACK carries the SDP of the media server, send a third 200 OK message to the console, wherein said third 200 OK message carries a SDP that has no practical effect, send an INFO message, which is a command for creating a multimedia conference, to the media server, and add the at least two user equipment into the conference to complete switching of the CTD service to the multimedia conference service; each of the at least two user equipment is configured to receive the re-INVITE message and return a first 200 OK message, wherein said first 200 OK message carries the SDP of the corresponding user equipment; and the media server is configured to return a second 200 OK to the application server and create a multimedia conference, wherein said second 200 OK carries the SDP of the media server.