Research Of Routing Protocol And Realization Of Simulation For Opportunistic Networks

As a result of emergence of variant portable devices, opportunistic networks,which are evolved from mobile ad hoc networks (MANET), possess broad prospect ofapplication. Its concept comes from delay tolerant networks (DTN). Compared withMANET, intermittency of wireless networks is viewed as the inherent characteristicof its, and messages are forwarded during the opportunities of communicationsbetween nodes. Apparently, in opportunistic networks the arbitrary movements ofnodes cause end-to-end path made up of the nodes to be state of constantly changing,and the forwarding of message to have to suffer higher delay. Therefore the previousprotocols of MANET won’t run properly in the opportunistic networks. The researchis currently at the initial stage. This paper utilizes the characteristics of socialresearch design and implementation issues for routing protocols and movementmodels of opportunistic networks.The concept, characteristics, structure and some initial applications ofopportunistic networks are summarized. The routing protocols proposed in recentyears are summed up. Then the movement model of classical random and HCMM areintroduced.Most of existing routing protocols based on social characteristics need to addaddress information to each node, which means if sender don’t get addressinformation of recipient, the message contains so few information that theperformance is degraded. In this regard, a routing protocol based on historicalintervals of contacts is proposed in this paper. Intervals of contacts represent pausetime among meets of nodes. Its historical information reflects degree of relationbetween nodes interaction. The computational method of historical intervals which isused as a utility value in the routing algorithm is also proposed. According to thealgorithm, each node takes precedence of messages whose destination is neighbornodes, and then forwards news to others on the basis of the ascending utility order.Compared with Epidemic protocol and Prophet protocol, the results of experimentshow that for each aspect of performance indicators-delivery ratio, averagetransmission delay and bandwidth overhead-protocol behaves well.Many previous movement model based social concludes that nodes located indifferent communities are involved in social relations which nodes rely on to wanderthrough communities. But it is always directly initialized to numerical value. The opportunistic networks model based on Hunan University are designed andimplemented in the paper. Messages which would attract other nodes to come intocommunity of senders are regarded as a kind of dynamic social relations and noticesof events by model. And nodes would walk along the fixed path-route of map ofHunan University-between communities. The model is impletmented in the platformof ONE, and the results show that it reliably simulates the movement patterns ofhuman communities.