Signature caching techniques for information filtering in mobile environments

This paper discusses signature caching strategies to reduce power consumption for wireless broadcast and filtering services. The two-level signature scheme is used for indexing the information frames. A signature is considered as the basic caching entity in this paper. Four caching policies are compared in terms of tune-in time and access time. With reasonable access time delay, all of the caching policies reduce the tune-in time for the two-level signature scheme. Moreover, two cache replacement policies are presented and compared by simulation. The result shows that, when the cache size is small, caching only the integrated signatures is recommended. When the size of cache is greater than that of the integrated signatures, caching both of the integrated and simple signatures is better.