Research On Connectivity Restoration Strategy Of Wireless Sensor Networks

Wireless sensor networks(WSNs)are a key component of the cyber-physical systems(CPS)and the Internet of Things(IoT).WSNs are sometimes deployed in harsh environments and are easily damaged by the outside world,so the network is divided into multiple isolated partitions.In this case,the network needs an effective connectivity recovery strategy to restore the network to normal operation.Connectivity restoration is one of the basic issues of WSNs,which directly determines the network life cycle and other aspects of performance.The current connectivity restoration methods of WSNs mainly consider basic factors such as deployment costs,but lack effective ways to restrain delay,enhance network reliability,and balance network load.This will result in excessive network delay,low resistance to secondary damage,and short network life.In order to solve the above problems,this paper proposes two WSNs connectivity recovery strategies,the main contents of which are summarized as follows:1)This paper proposes a Load-Balanced and Delay-Constrained Connectivity Establishment(LDCE),which is used to solve the load balancing problem under the condition of delay constraint.This strategy improves the load balance of the network by not only considering the load balancing situation in the partitions but also the load balancing situation between the partitions,and controls the delay through a hybrid method of moving relay nodes and deploying static relay nodes.The goal of LDCE is not only to simply restore the connectivity of the divided network,but also to improve the load balance of the network and control the network delay.Finally,the superiority of the performance of the strategy is verified through experimental simulation.2)This paper proposes a Multi-Objective Connectivity Restoration(MOCR),which is used to solve the problem of network reliability and load balancing.This strategy divides all isolated partitions in the network into short-distance group,medium-distance group,and long-distance group based on the shortest Euclidean distance from the partition to the base station.In the short-distance group,the data flow distribution mechanism is adopted to make the partition of the group directly connect to the base station as much as possible;in the middle-distance group,the partition shape selection mechanism is adopted to enhance the network reliability;in the long-distance group,the traffic load balancing mechanism is adopted to balance the network traffic load.On the basis of ensuring the connection,this strategy reduces the connection cost,balances the network traffic load and improves the reliability of the network.Finally,the advantages of this strategy are verified through experimental simulations.