MBMS-MULTIMEDIA BROADCAST MULTICAST SERVICE

This article provides an overview of the multimedia broadcast/multicast service (MBMS) for universal mobile telecommunications system (UMTS) networks. We first outline the features of UMTS networks as defined by the 3rd generation partnership project (3GPP) in order to provide a background for the discussion to follow. We then present the overall MBMS architecture, the services that it provides to the users and the differences between the broadcast and multicast options. The implementation details of MBMS are explained in terms of the modifications needed to the network, the new signaling procedures required and the impact of MBMS on the radio part of the network. We then describe how the security architecture of UMTS is used to support content protection and key distribution for MBMS groups. We evaluate the prospects of MBMS by comparing it first with IP multicast and then with DVB-H, considered by many to be the closest competitor of MBMS. Finally, we conclude with a discussion of the technical and business challenges still faced by MBMS.