Adaptive Data Broadcasting Using Air - Cache

In the Data AirWaves Project at University of Maryland, we are integrating Direct Broadcast Satellite (DBS) systems with terrestrial networks to provide a hybrid and e ective communication substrate lying between data resources and remote/mobile user applications. Smooth integration of these two media balances the need for rapid data dissemination to very large numbers of clients and on{demand interactive data services. This paper describes the air{cache, a method for e ective data broadcasting and an algorithm which rapidly adapts the content of the cache based on the \misses" which result in explicit (on{demand) data requests. Simulation results show that the hypothesis of adapting based only on the misses performs quite reasonably and has very little deviation from a system that has complete information { both hits and misses. This material is based upon work supported by the Center for Satellite and Hybrid Communication Networks under NASA grant NAGW{2777, by the National Science Foundation under Grants No. NSF EEC 94{02384 and No. ASC 9318183, and by ARPA under Grant No. F30602{93{C{0177