Synchronized Broadcast in Cellular Networks

The problem of multi-cell broadcast in cellular structured wireless networks is considered. It is shown that mobile subscribers that traverse cell boundaries while a multi-cell broadcast is in progress can experience a number of negative eeects. These eeects include severe jitter during multimedia transmissions and possible loss of critical data in mobile computing applications. As a solution, we propose a paradigm called \synchronized broadcast" for cellular networks. To enforce synchronized broadcast, we develop protocols that minimize the maximum time diierence between the local delivery inception times of a broadcast message by a group of base stations. The solutions described here also reduce the need for retransmissions of broadcast messages; thereby conserving scarce bandwidth resources. Two classes of protocols are exhibited. The rst class, called basic synchronized broadcast (BSB) protocols, is developed under the hypothesis that at most one message is pending for broadcast at any instant in time within a cluster of cells. The second class of solutions, called synchronized totally ordered broadcast (STOB) protocols, address the more general scenario in which broadcast messages are generated independently and asynchronously by multiple sources.