Multicast mobility in SIP layer

Wireless mobility had been the topic of research and development due to the popular use of portable computers. Multicast applications for mobile hosts have been considered recently. This paper first introduces the previous work related to multicast mobility and presents some issues that exist in IP multicast mobility. We propose a new method for, multicast mobility in the session initiation protocol (SIP) layer and discuss how mobile SIP with multicast deals with these issues for multicast communication in the IP layer. The paper also describes the structure of the SIP multicast mobility that is independent of the IP layer and extends SIP functions to support SIP multicast mobility. The proposed method avoids problems exiting in the IP multicast mobility by shifting the concept of multicasting and mobility from IP layer to session and application layers.