Authors: Amir Rashid Chaudhary and Hassan Ahmed
In today’s telecommunication arena, conference call service is an indispensable audio/video calling tool. IMS is based on Internet Protocol which reduces cost and enables the rapid development of new state of the art services. This paper is an extension of our previous work and provides an innovative novel solution to an important problem of the graceful degradation of call quality for individuals engaged in a conference call. Presently all the individuals participating in a conference call through an IMS server have to share the same codec whether audio or video. In the event that the connection speed of a participant is unable to support the streaming requirements of the conference call; that participant is dropped from the call. The proposed system of seamless runtime codec switching presented in this paper can be used to implement a system where if a connection in a conference call is unable to support the requirements of video codec then that connection may switch to an audio codec at runtime but still remain a part of that call.
Keywords: IMS, OpenVCS, SIP/UDP, RTP, Codec Switching, Conference Call