Improvements To Distributed Data Storage And Query Algorithms Based On Geographic Hash Tables In WSN

Efficient storage and query of data is the key technology to improve the efficiency of the whole network in wireless sensor networks.At present,the distributed storage strategy based on date-centric storage,is becoming the mainstream.And one of the most widely used algorithms is based on the geographic hash table(GHT)algorithm.This paper deeply analyzes and studies the key factors affecting the data storage and query in wireless sensor networks and the existing problems of the traditional GHT algorithm,and then the improved GHT algorithm is proposed.In data storage stage,producer node will transmit data to the nodes that on the location of the nearest node from the Hash function(according to the actual s,ituation in a different environment).At this time,the storage node checks its own traffic,when communication beyond their threshold(the threshold is set depending on the circumstances),this storage node will calculated by the other function of the position located nearest node through Hash function,then producer node will search in accordance with greedy way to find the shortest path storage node.In this analogy,each storage node will calculate the real-time traffic,and make the same policy in its own communication traffic exceeds its threshold;In data retrieval stage,query node will follow greedy search the shortest path that the nearest data storage node.Finally,simulation results show that the improved GHT algorithm in network load balancing,communication consumption than the traditional algorithm GHT and another widely used distributed storage Double ruling algorithm.Effectiveness and reliability of the improved algorithm are proved in the simulation platform of MATLAB.Simulation experiments are conducted to compare with the performance of the proposed algorithm,GHT algorithm and double Rulings algorithm in terms of data storage,communication cost and energy-load.The simulation results show that the improved algorithm has a better performance than GHT algorithm and double Rulings algorithm in the case of saving overhead and balancing load.