Research On Complex Network Routing Protocols

There are a variety of complex networks in nature and social systems.Over the past two decades,researchers from various disciplines have made efforts to collect and visualize various complex networks,measure and model complex network structures,predict and control complex network dynamics.They obtained many interesting results and theories,which leads to the formation of the frontier field:network science.In recent years,the network theory and big data technology complement each other,and they are more and more widely applied to industry,showing a very clear application prospect.There are a lot of complex networks in the modern communication systems,such as Internet,telephone network and sensor network,which provide a lot of valuable data for the research of network science.In turn,the theory of network science provides strong theoretical guidance for the design and performance analysis of complex communication networks.In the communication network architecture,the routing protocol defines the basic rules of communication between nodes and the key mechanisms of packet transmission,which ensures the realization of network communication function and shows the critical position of routing protocol in the communication system.The quality of the routing protocol has a direct impact on the data transmission performance.Based on the theory of network science,we study the data routing problem in different types of complex communication networks.We aim to design new routing protocols and communication architectures.Our work may provide some theoretical reference for the design of modern communication network architecture.The specific work of this thesis is as follows:(1)The routing problem of bufferless communication network is studied.The complex network models are applied to the topology modeling of bufferless communication network;The effective routing protocol is applied to the bufferless data communication process;A random deflection strategy based on the delivery queue of neighbor node is proposed to reduce the packet loss rate of the bufferless transmission;The influence of packet generation rate,node forwarding capability,average node degree,degree distribution,number of nodes and routing control parameters on the performance of bufferless data transmission is discussed;The optimal routing parameters corresponding to the smallest packet loss rate and average arrival time are obtained by simulation.(2)The routing problem of complex networks of both fixed and mobile nodes is studied.A hybrid network model with fixed nodes as the core network layer and mobile node as the users is proposed;The phase transition from free flow to traffic congestion is analyzed;A direction based random rewiring strategy and a minimum-load routing strategy are proposed;The influence of mobile node speed,number of mobile nodes,random reconnection probability and degree distribution of fixed nodes on network capacity is studied by simulation experiment.(3)The routing problem of multi-layer complex networks is studied.A two-layer communication network model composed of logical layer and physical layer is proposed.The logical layer runs the shortest path protocol and the physical layer runs a biased random walk strategy.The dependence of the network lifetime and number of arrival packets on the random walk parameters is analyzed.The influence of the node degree distribution of fixed nodes on the network transmission performance is studied.The topology of the upper and lower layers is optimized by the link-deleting strategy to improve the transmission performance of the network.