Research On Hybrid Routing Mechanism In The Opportunity Network

Opportunistic network is an Ad Hoc network, which source node and destination node cancommunicate without a connecting link. Opportunistic network is intermittently connected ordisconnected, so the traditional wireless Ad Hoc network routing protocols unable to run under theenvironment. Therefore, the research of opportunistic network routing has important theoretical andpractical value.Firstly, the paper research and analysis the routing strategy in opportunistic network, introducethe existing routing strategy classification and typical routing algorithm corresponds to related routingstrategy, then analysis the advantages and the problems of algorithms.Secondly, based on the previous introduction, the paper proposes a routing algorithm calledED_PROPHET, which takes encounter duration into consideration. The algorithm utilizes historymeets, encounter frequency and encounter duration between node pair to determine the next hop ofthe message; for the limited cache space of node, ED_PROPHET adds a cache management strategy,which utilizes the survival time and the number of copies of the message in the network to determinewhether messages need to remove and its position in the cache.Thirdly, the paper proposes an Urban Infrastructure-based Hybrid Routing (UIHR in short). Thealgorithm uses the infrastructure as a relay to translate message. The infrastructures, which aredeployed in the areas with larger daily flow of people, can contact with more nodes, then translatemessages more quickly, and improve the message delivery rate and reduce the message delivery delay.The algorithm also adds the feedback mechanism of delivered message to reduce the number ofmessage copy in the network at the same time, thereby reduces the consumption of network resources.Finally, ED_PROPHET and UIHR algorithms are simulated in ONE (Opportunistic NetworkEnvironment) simulation platform. Simulation results show that compared with the classic hybridrouting algorithm, ED_PROPHET algorithm gets higher message delivery rate, lower messagedelivery delay and resource consumption. In the urban environment, UIHR algorithm gets betterperformance than ED_PROPHET algorithm.