The Fault-tolerant Topology Control Algorithm For Wireless Sensor Networks

Being the important carrier to popularize Internet of Things,Wireless Sensor Networks is a modern and new technology to collect,organize and transmit information and it is one of the hotspots in the field of wireless communication.Due to the limited energy of sensor nodes and harsh environment for deploying,the situation of node or link failure is very easy to appear in the network which will easily hinder the connectivity of the network and greatly influence the normal operation of it.Meanwhile,topology control is one of the necessary means to realize the normal working of the network.On the one hand,topology control can control the energy consumption to achieve the purpose of saving energy.As a result,it can prolong the operation time of the network.On the other hand,it can deal with the failure behavior of the node or link and improve fault tolerance.And the normal working of the network is guaranteed by improving the redundancy and fault tolerance and establishing a reliable and stable network topology.Therefore,it is very significant for the wide application of Wireless Sensor Networks to design an algorithm of topology control with the characteristics of energy saving and fault tolerance.The main research work of this paper is as follows:The optimization goal of many existing topology control algorithms is very single.In order to adapt to the increasingly wide application requirements of the network,two different energy-saving and fault-tolerant algorithms of topology control are proposed in this paper.Finding a balance between energy efficiency and fault tolerance is the main aim for the design of the algorithm,and the main goal of this paper is to design a network topology with multiple optimization performances.Topology control is a pretty critical way to improve the efficiency of energy utilization and the foundation to produce redundancy in Wireless Sensor Networks.There are several researches discussing the topology control problem that only focuses on the optimization of a single goal instead of multiple targets,so the fault-tolerant topology control algorithm of k-disjoint paths which takes into consideration both energy efficiency and fault tolerance is presented.Frist of all,the sink node sends communication messages of different colors to the other nodes in the whole network,after the sensor node receives the communication messages with k different colors,and k disjoint paths are supposed to be constructed from sensor nodes to the sink node which ensuring that the network has a certain redundant link.Secondly,energy consumption of the path,the standard deviation of the nodes' power in the path and the number of the path hop are three factors to measure the path quality.In order to select the path with energy efficiency and other properties,a multi-objective programming is established according to the three indicators mentioned above.And the programming can be solved in use of intelligent optimization algorithm and the paths can be optimized and selected depending on the different values of k.And choosing better paths depends on the k value.Simulation results show that our algorithm can reduce the energy consumption,prolong the network lifetime and improve the fault tolerance.Topology control is one of the key technologies to extend the life of the network.As a result,a double cluster head-based fault-tolerant topology control algorithm(DCHFT)is presented which takes both network life and fault tolerance into consideration.Firstly,the algorithm uses the agglomerative nesting algorithm based on nodes' location to divide the large-scale network into several subareas,which completes the clustering of the network.However,the number of clusters is determined by the number of optimal clusters.Secondly,according to the factors such as the distance between nodes and energy consumption,the formulas of selection of the main cluster head and the vice cluster head are defined,and the main cluster head and the vice cluster head are respectively responsible for communication tasks in clusters and the inter-cluster.Therefore,the network with double cluster heads obviously reflects some fault tolerance compared with a single cluster head.Finally,the simulation results show that DCHFT can reduce energy consumption,prolong the network lifetime and improve the fault tolerance,compared with the typical clustering algorithm like LEACH and EEUC.