Research On Opportunistic Routing In Moble AD HOC Networks

Mobile Ad hoc network is a kind of new wireless mobile network, in which the node are mobile, and it doesn't depend on a fixed base station and it can take mobile communications and computer networks together to realize rapid deployment. Usually nodes in the network are portable terminals and information exchange mechanism in the network is like packet exchange mechanism in computer networks.Mobile Ad hoc network routing design has always been a difficult and important problem. Compared with wired networks mobile Ad hoc network routing has many challenges in many aspects, including node mobility, network topology variability, multi-hop transfer, wireless channel unreliability and so on. In recent years, a routing technology called opportunistic routing has been proposed and has gained widespread concern. A distinct difference with the traditional route is that the opportunistic routing does not use a fixed route: the relay node independently choose the forwarding nodes according to routing protocols. This delivery process continues until the destination node receive the packet. Each transmission have more opportunities to be received and delivered than the traditional routings, so the opportunistic routing gets its name.The main contributions of our work are:(1) proposed a new opportunistic routing method CFP(opportunistic routing considering the future paths). In this routing, the situation after a certain number of hops in the future will be considered, and hence the node makes the decision whether it should compete to forwarding this packet. Compared with the opportunistic routings using greedy forwarding strategy, CFP aims to effectively reduce the cases of non-forwarding nodes in the follow-up hops, and it can raise the success rate of data transmission and network throughput, thus the network has better reliability.(2) We presents a new opportunistic routing in real-time streaming media operation transmission: AGOR(adaptive grid opportunistic routing). To fit the characteristics of the streaming media operation transmission over mobile Ad hoc networks, we combine the advantages of grid routing and opportunistic routing to present our AGOR . AGOR dynamically assigns a number of quadrate grids as candidate region for packet relaying, and changes nodes'dynamic characteristic into grids'geographical stillness therefore be a very good dynamic transmitting performance can be achieved; also in AGOR handshake signals are no longer needed within the grid and the previous network topology management is simplified, so it is appropriate to be applied in the streaming media operation.We use OPNET to simulate the performance of our routing CFP and AGOR. Compared to the existing routing technology, we find that our new routing technology has a certain increase in key performance.