Comparative study of broadcast and multicast in 3GPP and 3GPP2 networks

Multicast can greatly save network bandwidth because only one copy of data is transmitted in the shared paths. Applications such as video conferences and network games usually can benefit from multicast. Although mobile multicast has been studied for years, it is still a challenge and has not been widely realized in today's Internet. Both 3GPP and 3GPP2 have defined architectures and protocols for multicast. This paper presents the multicast architectures and operations defined in 3GPP and 3GPP2. Besides, this paper also provides a systematic comparison of them. In addition to system architectures, various issues including mobility, QoS, and security are discussed. Moreover, we discuss the challenges in radio resource management (RRM), power control, scalability, and complexity. This paper could be a reference for those seeking the perspective often difficult to obtain from standards specifications.