Mobile Intelligence

24.7 SUMMARY

This chapter classifies the existing data-centric mechanisms into basic, data-replica, load-balanced, and hierarchical management categories, according to their goals and designing concepts. Then the chapter reviews the basic concept and the strategy of each mechanism. Finally, we point out some possible future directions and open issues related to the data-centric storage problem. In the basic data-centric category, the GHT mechanism that simply applies hashing function to derive the location of data-centric node is reviewed. To improve the fault-tolerance capability and the query efficiency, some mechanisms that fall in the data-replica category are reviewed. These mechanisms are further classified into ring-based, tree-based, and zone-based classes, according to the applied topologies. Since the network lifetime is one of the most important concerns in designing any protocol for WSN, some other data-centric mechanisms that fall in the load-balanced category are reviewed. Finally, the chapter reviews four data-centric mechanisms that aim to reduce the network traffic and provide efficient queries. These mechanisms belonging to the hierarchical management category are further classified into zone-based and cluster-based classes.

Although there are a number of existing data-centric mechanisms proposed in the literature, however, none of them considers the network environment with multiple sinks, which might initiate the same or similar query requests to the same data-centric ...