Efficient Index Caching Schemes for Data Broadcasting in Mobile Computing Environments

• Authors: Jen-Jou Hung;Yungho Leu
• Venue: DEXA '03 Proceedings of the 14th International Workshop on Database and Expert Systems Applications
• Year: 2003

Data broadcasting is an efficient technique for disseminatingdata in mobile computing environments. To reducethe power consumption of the mobile clients, index is usedto expedite the access of the disseminated data. In our opinion,caching the indices on the mobile clients can furtherreduce the tuning time of the mobile clients. In this paper,we propose two policies to reduce the tuning time of the mobileclients. The lower level index first policy tends to cachethe leave index nodes of the index tree while the cut planefirst policy caches the cut-plane of the index tree. Accordingto our experiments, both policies have significantly reducedthe tuning time and the access time of the mobile clients.Furthermore, the cut plane first policy prevails in the casewhere the cache size of the clients is small, or when theclients have a uniformly distributed access pattern over thebroadcast data items.