Scheduling information broadcast in asymmetric environment

Abstract

With the increasing popularity of portable wireless computers, mechanisms to efficiently transmit information to such clients are of significant interest. The environment under consideration is asymmetric in that the information server has relatively larger bandwidth to communicate to clients than the clients have to communicate to the server. Many applications suit to such environment, some even do not require the clients to send any data (requests) to server. Experience has shown that in such environments, the server should broadcast the information periodically. Many researchers have shown their interest in this area and their nature of work covers a broad horizon. The key to efficient broadcasting lies very much on the way the schedule of broadcasting information is prepared by the server. Many researchers have proposed different schemes but too few talk about optimality of information scheduling. Also most of them assume the medium to be perfect and do not take the transmission errors into account. Besides, an interesting variation of the problem would be to broadcast over multiple channels which has not been given much attention. This thesis analyzes the solutions to these problems. It also gives a couple of algorithms and evaluates their performance using simulation. It also compares the simulation results with the lower bounds obtained by analysis of these problems.