| In the condition of an unexpected disaster or a terrorist attack, which leads to the failure of infrastructure and network couldn't work, it is extremely important to reconstruct the network quickly. As a self-configuring infrastructureless network, Mobile Ad hoc network can be fast and easily deployed. By virtue of Ad hoc network, it is possible to rapidly deploy a temporary network in Disaster Area. Such temporary networks serve the people, provide convenience for rescue and reduce the damage caused by the disaster. Ad hoc networks bring great convenience and flexibility for deployment and applications, meanwhile with some negative factors, such as temporary connectivity, unpredicted change of the topology, interrupted data transmission. Therefore, it is a great challenge for research and design of the networks protocols. In order to make the application of Ad hoc networks to be not constrained by the surrounding environment, this thesis did the research work around several aspects. The specific contributions are described as follows.(1) Geological disasters always shift landforms and form many obstacles. This thesis is focused on issues that obstacle might bind the movement of nodes and block the radio transmission in Ad hoc networks, and researched on the simulation of the obstacle environment. It proposed a discrete-time Markov chain model for obstacle Ad hoc networks, called ODM, based on the theory of Markov stochastic process. By the analysis of ODM, we could forecast several performance parameters, such as the probability that an edge was valid, the average number of valid-edges and the probability of a request packet found a valid route. Compared with n-SRBDM, the calculated value of ODM is closer to the actual value; therefore, ODM is more suitable for imitating the node moving in environment with obstacles.(2) To solve the problems of dense Ad hoc networks, such as low utilization of space and low throughput, research work on topology control has been done. Based on computational geometry, the proposed algorithm constructs a dense Ad hoc backbone network (TBN). TBN consists of building the backbone network, setting the gateway sequence and reconstruction. Theoretical analysis and simulation results showed that TBN was a two-connected structure, and its connectivity or number of edges had little influence on node density. (3) Through the research work on routing algorithms for Intermittently Connected Mobile Ad Hoc Network, we proposed an efficient Variable Ferries Routing scheme (VFR) using store-and-forward techniques of delay tolerant network (DTN). This paper designed the ferry path as a multi-objective optimization problem, modeled the message delivery process as a queuing system, and solved the problems of path design and ferry number determination. Compared with Epidemic, PROPHET and OPWP, simulation results demonstrated that VFR minimized the message delivery delay and the overhead ratio. Moreover, VFR reduced resource requirements in ferries resulting in increasing ferries efficiency.(4) Make research on routing algorithms in VANET. With the help of game theory, this paper built the message forwarding game model to solve the problem that the waste of resources caused by large number of forwarding messages when the density was high. A routing algorithm was proposed, called Macro-Micro Game routing algorithm (MMGR). In the intermittent connection situation, we used the store-and-forward scheme and Message Forwarding Game (MFG) to solve the problems occurred with dense nodes. Finally, Simulation results of comparing our scheme with existing routing algorithms, such as Epidemic and PROPHET, demonstrated that MMGR provided better message delivery ratio and reduced the overhead ratio...
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