Study On Topology Control And Algorithm Based On Theory Of Scale-free For Wireless Sensor Networks

This paper uses the scale-free theory to build network topology. The topology builtcan improve the wireless sensor networks (WSNs) fault tolerance for random failure, andalso can prolong the network lifetime. The mathematical model about topologicalparameters is established. Based on the model, the optimization topology controlalgorithms are researched to reduce the energy consumption of communication path andoptimize the ability of tolerating invasion. And the network anti-destroying ability can beenhanced effectively.Firstly, for the issue of path energy consumption, this paper established anoptimization model of network path energy consumption based on the mode of multi-hop.Then the value law of the node degree that can minimize the enerry consumption ofnetwork is deduced. According to the optimal value of nodes, the network topology wasbuilt based on a fitness model which can control the network average node degree. Thena scale-free fault-tolerant topology control algorithm with the characteristics that canminimize the path energy consumption is put forward. The simulation results show thatthe algorithm can reduce the path energy consumption in the network and then make thenetwork energy-efficient.Sencondly, the algorithm above can reduce the path energy consumption of network,but scale-free topology is extremely fragile when suffering form the deliberate attacks,then we build the mathematical model about performance parameters of intrusiontolerance. The model gives the coupling relationship between the the power-law exponentand the intrusion tolerance. According to the Possion network model with node batcharrival and attraction degree rules, this paper presents a wireless sensor networksevolution model. Based on this model, the topology control algorithm withintrusion-tolerance optimization characteristics is designed in this paper. Simulationresults show that the new algorithm can not only effectively tolerate random failures ofnodes, but also can improve network capacity of tolerating deliberate attack intrusion.Lastly, in order to investigate the issue of the scale-free network’s dynamic anti-destroying ability. A scale-free cascading failure model is built based on function ofnodes degree, the effect of critical threshold on cascading failure is analyzed. The criticalthreshold can be changed by the network parameters, and the network parameters affectthe scale-free network dynamic anti-destroying ability in turn. The experimental resultsshow that the network’s parameters (edge number added in unit time and the powerexponent) are positively correlated with the network’s invulnerability for cascadingfailure. dynamic anti-destroying ability is positively related with the newly added edgesper unit time and power-law exponent. Namely, the more edges added, the higher thepower exponent is, and the network’s invulnerability for cascading failure is stronger.