Data broadcasting strategies over multiple unreliable wireless channels

Data communication in a mobile environment involves a stationary database server disseminating information to a large collection of 'mobile clients' via wireless transmission media. One effective way to disseminate database information via narrow bandwidth wireless media to the mobile clients is to periodically broadcast the database over the 'air'; individual clients will then 'catch' their interested data on the fly selectively. Wireless transmission, however, is vulnerable to noise and signal distortion. Furthermore, a client might not aware of when its interested data will be broadcasted and might fail to catch the data at the appropriate moment. In either situation, it has to wait for the next broadcast cycle, severely affecting the performance of the database access. In this paper, we describe a spectrum of data broadcasting mechanisms in a mobile environment over noisy media. The data broadcasting schemes are based on replication and partition techniques that distribute the broadcasted data over multiple wireless media. We evaluate the relative performance of the broadcasting schemes analytically, as well as through simulation experiments. The simulation results are also studied and verified with the analytical results.