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Semantic Data Broadcast for a Mobile Environment Based on Dynamic and Adaptive Chunking
October 2002 (vol. 51 no. 10)
pp. 1253-1268

Abstract—Database broadcast is an effective and scalable approach to disseminate information of high affinity to a large collection of mobile clients. A common problem of existing broadcast approaches is the lack of knowledge for a client to determine if all data items satisfying its query could be obtained from the broadcast. We therefore propose a semantic-based broadcast approach. A semantic descriptor is attached to each broadcast unit, called a data chunk. This semantic descriptor allows a client to determine if a query can be answered entirely based on broadcast items and, if needed, identify the precise definition of the remaining items in the form of a “supplementary” query. Data chunks can be of static or dynamic sizes and organized hierarchically. Their boundary can be determined on-the-fly, adaptive to the nature of client queries. We investigate different ways of organizing the data chunks over a broadcast channel to improve access performance. We introduce the data affinity index metric, which more accurately reflects client-perceived performance. A simulation model is built to evaluate our semantic-based broadcast schemes.

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Index Terms:
Mobile databases, semantic-based broadcast, dynamic chunking, adaptive chunking, answerability.
Ken C.K. Lee, Hong Va Leong, Antonio Si, "Semantic Data Broadcast for a Mobile Environment Based on Dynamic and Adaptive Chunking," IEEE Transactions on Computers, vol. 51, no. 10, pp. 1253-1268, Oct. 2002, doi:10.1109/TC.2002.1039851
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