Design And Simulated Implementation Of Routing Mechanisms In Campus MSN

The gradual maturity in mobile communication technology and the wide application in intelligent terminal equipment provide firm foundation for the appearance and development of Mobile Social Networks (MSN). As a new application pattern, campus MSN is an expansion of the real social network in the field of the wireless communication, which forwards message data hop by hop between different users according to the people’s mobility and local connectivity. Besides, users’movement has a certain regularity which is ensured by the social relationships between nodes, stable and predictable. Therefore, sufficient consideration for social relationships could improve the routing performance of campus MSN.In this thesis, through the study of the sociality and mobility for mobile social networks, the unicast routing mechanism and multicast routing mechanism based on communities are designed. First, considering the authenticity of the simulation process, an improved students’ daily activity mobility model is given to simulate users’ mobile traces in the campus network. Secondly, according to the contact duration, contact frequency and contact interval of mobile users, a kind of friend relationship metric used to measure the closeness between nodes is proposed. SE social metric is proposed for forwarding decisions after the interest similarity and meeting probability of nodes are defined. Moreover, according to the social experience analysis, a community discovery algorithm based on the network clustering coefficient and the overlap degree of shared neighbors is presented to obtain community collections used in the routing process. To further improve the routing performance, both the node buffer management mechanism and the punishment and incentive mechanism are designed. On the basis of above researches, a community based unicast routing mechanism is designed considering multiple routing objectives. The mechanism utilizes the Brownian motion behavior and turbulent rotational motion behavior of gas molecules, and finds the optimal forwarding node either in or across network communities using appropriate routing strategies based on a single copy model of the message. In addition, in order to reduce the network overhead in the message multicast process, which is as our main objective, a community based multicast routing mechanism is designed. Its main idea is that for the purpose of destination nodes carried by the current message, intermediaries will be found which are in favor of the most destination nodes of the message. It means to generate a dynamic multicast tree by wait-compare-split strategy so as to realize multi-destination routing in the community structure.The poposed unicast routing and multicast routing mechanism have been simulated, and then performance comparison is fairly conducted between them and the benchmarks on several indexes in this thesis. The results show that the routing mechanisms designed in this thesis have respective advantages on different performances, and both have certain advantages on the message delivery rate and network overhead aspects, etc. Hence, they are feasible and effective.