Research On The Architecture And Techniques For Delay-Tolerant Networks

Internet has obtained great achievements in the connection of heterogeneous nets. With the development of the science and technology and the deepening of various researches, many new kinds of networks start to appear, such as Terrestrial Mobile Networks, Military Ad hoc Networks, Interplanetary Internet, Wireless Sensor Networks and so on. These networks have the features of long or variable delay, high error rates, intermittent connectivity and limited resources. They were called"challenged networks".They have brought great challenges to the Internet. So, a new type of general used network architecture is needed. DTN is one alternative, it is an abstraction of several kinds of challenged networks.At first, this thesis analyzed the application background and research situation of DTN and introduced DTN architecture in detail. On this basis, the thesis studied the bundle protocol, convergence layer protocols and DTN's custody transfer. Then it researched the current DTN routing strategies, different routing strategies are suitable for different network scales, topologies, network resources and node mobility. Then it proposed a method to design routing strategy for special DTN scenes.After, the thesis summarized severel congestion control methods. On this basis, it proposed a kind of thought of congestion control based on statistical service priorities. At last, the thesis builded DTN scenes with OPNET (one kind of network simulation software) and compared the network performance of custody forwarding and common forwarding modes, such as end-to-end delay, user date rate and data successful arrival rate, etc.