Research On Data Management In WSNs

wireless sensor network is a kind of wireless communications network composedof a large number of senor nodes distributed in the monitoring area that are capable of dataawareness, wireless communications, data calculation and processing. With thedevelopment of internet technology, embedded technology and wireless communicationstechnology, the wireless sensor network has undergone tremendous growth. Comparedwith traditional network, the wireless sensor network is characterized by large quantities ofnodes, limited energy resources and rapid change in network topology, and thesecharacteristics have made research in approaches to efficient management of wirelesssensor network data a tough problem and hot topic in this area.This paper combines the context, significance and current research situation ofwireless sensor data management in exploring its several major aspects, including datamodel, data mode, data storage, indexing technology, distributed query technology, andanalyzes both the strengths and weaknesses of three storage technologies, highlightingdata-centric, geographic hash function-based storage algorithm-the Geographic HashTable (GHT), which avoids flood operations in executing query commands and drasticallylessens the blindness of data transmission. Nevertheless, GHT algorithm is unable tosatisfy the system that has higher demands for energy consumption and query delay.With an aim to improve efficiency, reduce node energy consumption and extendnetwork lifetime, this paper puts forward the event priority-based GHT distributedalgorithm which, in terms of storage policy, reduces energy consumption during storagethrough dividing the whole area covered by wireless sensor network into sectors, enableshigh-priority events closer to query nodes and easier to be found by defining priorities. Interms of routing policy, it improves geographical location-based routing algorithm–theGreedy Perimeter Stateless Routing (GPSR), and when selecting the next forwarding node,it makes use of energy and distance which jointly decides on routing and chooses routingnode, takes event priorities as the weights reference for choice of routing by energy anddistance, and resolves the hot issues in GPSR routing.In its concluding part, through experimental simulation and comparing the averageenergy consumption of event priority-based GHT algorithm which divides differentpartition numbers with that of GHT-based storage algorithm in networks of different sizes,this paper maintains that, when the divided partition numbers are optimum, the eventpriority-based GHT algorithm can effectively reduce storage energy consumption. And through comparing the average delays of the priority events in GHT-based algorithm andevent priority-based GHT algorithm in various network sizes, it can be concluded that theevent priority-based GHT algorithm can effectively reduce the delay of high-priorityqueries.