Toward Optimal Replication for Hierarchical Location Management in Wireless Systems
نویسندگان
چکیده
The location information of users can be replicated at various databases in a hierarchy to improve the efficiency of call lookups at the expense of increase in update and storage cost. In this paper, we systematically investigate this problem and propose two solutions. The first solution has optimal lookup and update cost, but the execution time could be exponential to the number of databases. The second solution makes some assumptions and then uses dynamic programming to tackle this problem. Its execution time is dramatically reduced with the result being less optimal. Finally, to further improve efficiency and reducing storage requirements, we propose the incorporation of clustering techniques.
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