| The interconnection between Mobile Ad Hoc Network and Internet can expand the application scope of MANET.As the core technology for realizing the interconnection between MANET and Internet,the gateway discovery algorithm has become a hot topic in wireless communication technology.Although there are many algorithms and models proposed for gateway discovery,there is still a need for further research on the distribution scenario of mobile nodes,the physical distance between mobile nodes and gateway nodes,and the optimization of the location of gateway nodes.Therefore,in this paper,in terms of gateway discovery performance,the gateway discovery algorithm has been deeply studied and analyzed,and then a gateway discovery algorithm is proposed to make it not only consider the distribution of mobile nodes,but also take different gateway discovery strategy according to different distribution states,and adjust the position of the gateway node according to the node distribution,so that the gateway node can not only meet the communication requirements of the mobile node in time,but also improve the network communication quality and other performance indicators.The main research results of this article are:(1)The mathematical definition of gateway discovery is proposed,and from this definition,the AODV protocol used in the establishment of paths between nodes in MANET is introduced in detail.The key factors in the adaptive gateway discovery algorithm(the number of gateway nodes,the location of the gateway nodes,and the radius of the gateway advertisement)are analyzed through the distribution of nodes in the network topology scene,and the influence of these factors on the performance of the gateway discovery algorithm is proposed.(2)A three-gateway adaptive gateway discovery algorithm based on DV-Hop positioning is proposed.In the scenario where a large number of mobile nodes are evenly distributed,according to the principle of the DV-Hop positioning algorithm,the position of the mobile node is estimated by using the position of the gateway node and the number of hops from the mobile node to the gateway node,and the gateway node estimates the position of the mobile node according to the information and its own location information calculate the actual distance between the mobile node and the gateway node.By comparing the actual distance between the three gateway nodes and the mobile node,the gateway node closest to the mobile node is determined to realize its interconnection with the mobile node.Through the above way between mobile nodes and gateway nodes interconnected and single gateway implementation of mobile nodes and gateway nodes interconnected way,verify that the algorithm in network throughput,the entire network in the entire network,the network time delay,data packet delivery ratio and so on the superiority of performance indicators.On the determination that the gateway node periodically sends the gateway announcement information range,it is determined whether the node that receives the gateway advertisement message needs to forward the announcement message through the mobile node position and the moving speed field of the mobile node included in the gateway announcement information,thereby achieving the purpose of adaptively adjusting the gateway sending gateway announcement scope.The algorithm reduces the overhead of sending control packets,and improves the overall communication quality of the network.(3)This paper proposes a gateway discovery algorithm based on K-mean algorithm to optimize the position of gateway nodes.In the scenario where mobile nodes are distributed in the form of clusters,according to the idea of K-mean clustering algorithm,the mobile node is positioned by the DV-Hop positioning algorithm mentioned in the previous chapter,and the location of the mobile node is determined based on the location.The mobile node is divided into three clusters.These three clusters are relatively far apart and the nodes within the cluster are relatively compact.By locating the position of the center node for each node in the cluster,the position of each gateway node is deployed,so that the three gateway nodes are respectively located at the center of the nodes in the three clusters.After deploying the positions for the three gateway nodes,adaptive gateway discovery of the three gateways is performed.This algorithm can achieve better network coverage,shorten the connectivity from the whole actual distance between mobile nodes and gateway nodes,so as to shorten the data transmission path,improve the network throughput of the whole network,reduce the network transmission delay,improve the efficiency of packet transmission.Based on the summary of existing gateway discovery algorithms,this paper proposes an adaptive gateway discovery algorithm based on DV-Hop positioning algorithm and a three-gateway discovery algorithm based on K-mean algorithm.A new idea and method are proposed for the gateway discovery algorithm,which provides a certain theoretical basis for the improvement of the gateway discovery algorithm and its future research and practice. |
PDF Full Text Request