Conference Paper

Broadcasting and Prefetching Schemes for Location Dependent Information Services.

DOI: 10.1007/11427865_3 Conference: Web and Wireless Geographical Information Systems, 4th InternationalWorkshop, W2GIS 2004, Goyang, Korea, November 2004, Revised Selected Papers
Source: DBLP


The results of location-dependent queries(LDQ) generally depend on the current locations of query issuers. Many mechanisms,
such as broadcast scheme, prefetching scheme, or caching scheme have been developed to improve system performance and provide
better service for location dependent information services(LDISs). However, the client’s mobility may lead to inconsistency
problems. In this paper, we introduce the broadcast-based LDIS scheme(BBS) in the mobile computing environment. In the BBS,
broadcasting data items are sorted sequentially based on their location and the server broadcasts the location dependent data(LDD)
without additional indices. Then we present a data prefetching scheme and OBC(Object Boundary Circle) in order to reduce the
client’s tuning time. The performance for the proposed scheme is investigated by various environmental variables such as distributions
of the data items, average speeds of the clients and the size of the service area.

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