Efficient index caching schemes for data broadcasting in mobile computing environments

Data broadcasting is an efficient technique for disseminating data in mobile computing environments. To reduce the power consumption of the mobile clients, index is used to expedite the access of the disseminated data. In our opinion, caching the indices on the mobile clients can further reduce the tuning time of the mobile clients. In this paper, we propose two policies to reduce the tuning time of the mobile clients. The lower level index tree while the cut plane first policy caches the cut-plane of the index tree. According to our experiments, both policies have significantly reduced the tuning time and the access time of the mobile clients. Further more, the cut plane first policy prevails in the case where the cache size of the clients is small, or when the clients have a uniformly distributed access pattern over the broadcast data items.