Research On Information Synchronization And Multicast Technology Of Dynamic Wireless Mesh Network

The wireless mesh network(WMN)discussed in this article is a supporting mobile node,wide-coverage wireless backbone network based on the IP protocol.This kind of network has the characteristics of scalability,robustness,easy to deploy and supporting for the entire network movement.This type of network is widely used in special environments such as tactical communication systems and emergency communication systems,and it is an important form of communication network.Information synchronization and multicast is an important one-to-many or many-to-many communication pattern,its implementation methods directly affect the performance of the network.The research originates from the project named "Research on Wireless Mesh Network Information Synchronization and Multicast Technology",which is a collabora-tive project between our laboratory and an institute.This topic studies how to ensure the stability of the information synchronization system or multicast tree architecture in an environment where the location of WMN nodes may change frequently or even the topology structure often changes.Main tasks of the study are as follow:Firstly,the related technologies of normal WMN,multicast,and tactical communication network are introduced.The existing hierarchically clustered multicast routing protocols,cluster head election algorithms,and multicast tree recovery algorithms are investigated and analyzed.Secondly,the problem of multicast tree construction in mobile environment is studied.From the perspective of improving the transmission efficiency of node information synchronization and reducing the impact of nodes leaving and joining on the entire network,a method of hierarchically clustering the network according to the physical location of the nodes is proposed.According to the node's moving attributes,out-degree and transmission delay,the concept of node instability is proposed.Based on the node instability,the method of election of cluster heads and backup cluster heads is put forward.And on the basis of the method,the construction algorithm about intra-cluster transmission tree and intercluster multicast tree is proposed.Finally,the problem of how to restore the function of the multicast system after the node leaves the network is studied.In order to reduce the impact of node departure on the function of the multicast system,a degree-constrained multicast recovery algorithm is proposed.Its core idea is to quickly restore the connectivity of the network topology by backing up neighboring node for the nodes,thereby restoring multicast system functions.Simulation results show that the algorithm proposed in the research can improve the stability of the cluster head in the mobile environment,thereby ensures the stability of the multicast tree,and can effectively reduce the multicast recovery delay.