The Research Of Data Fusion Protocol In Wireless Sensor Network Based On Mobile Agent

With the people's desire of getting well know the environment that around us, wireless sensor networks, which is a new type of network and computing technologies, come into being. It may transfer the changing information in material world to the people continuously and effectively, and provide us various forms of data resources and services. The characteristics of self-organizing, mini-size, low cost and flexibility give it a very broad perspective in many fields such as military affairs, environment science and business etc. The nodes of the sensor networks always use batteries to supply electricity, but the electricity energy in the batteries is limited. Hence, compared with other aspects, energy saving is an urgent problem to be solved. Due to its advantage performance in energy-saving, data fusion protocol now has become a focus in wireless sensor networks. And directed diffusion is one of the protocols.Summarizing the characteristics of wireless sensor networks, this paper analyzes the principle of directed diffusion deeply, and sum up some of its limitations. In order to overcome the disadvantages of the traditional distributed data fusion route, the dissertation implements mobile agent-based directed diffusion by introducing the mobile agent into wireless sensor networks. MADD does not have the energy balance, or restrain the flooding of interest messages and exploratory datas. Based on these considerations, the paper proposes an improved protocol named IMADD. Considering the remaining energy of nodes and the shortest path, IMADD realizes energy balance of the networks, and reduces forwarding counts of the interest effectively and energy consumption, by adding Energy Threshold and Minimum Hops Count into the head of interest packet. In addition, a mechanism used to limit flooding is proposed in the data exploratory stage of IMADD to restrain the flooding of exploratory datas effectively, and to decrease energy consumption and extend the lifetime of the whole wireless sensor networks.Finally, IMADD is simulated through the well known NS-2 simulator, and compared with MADD and directed diffusion. The results show that the IMADD protocol has more energy-efficient and better network latency in guaranteeing quality of services.