Reliable Transport Protocol Based On Data Aggregation In Wireless Sensor Networks

Wireless sensor network technique was used in volcano monitoring, forest fire prevention and gas monitoring fields with its low data rate, low cost, low energy consumption character. It has become a hot topic for research. In most of the applications, the reliable data transmission under limit data rate is a crucial issue. While, related work has little consideration about the small data characteristic, this causes low performance while transmitting data at a higher rate.According to these properties, this paper presents a reliable transport protocol based on data aggregation technique in wireless sensor networks. It mainly has three modules: routing, data aggregation and rate allocation. The routing module sets up the path from source to sink according to expected transmission times. And it updates and maintains the route while network changes. The new definition of packet sequence number can support aggregation scenario. The data aggregation module combines the small packets into a big packet in order to reduce net load and overhead, so as to achieve large capacity and high reliability. The rate allocation module allocates the upload rate in order to avoid congestion based on expect transmission times, interference nodes'number and child nodes'number.We set up a 9-nodes test-bed in our laboratory, implement our reliable transport protocol and make performance evaluation. It indicates that, our aggregation strategy reduces more than 30% packets'transmission times. Rate allocation can guarantee all the nodes get a deliver ratio over 80%, and half of which can reach 99%. All the nodes can receive requested number of packets per second to satisfy the reliability requirement.