Researches On Routing Protocol And Application In DTN

Due to the limitations of physical equipment and geographical environment in many application scenarios, the conventional routing mechanism is applicable no longer. In order to overcome this issue, Delay Tolerant Network with new data transmission mode was proposed which does not require a stable network connection and meets the needs of actual network under the bad environment. But DTN still faces many problems in practical applications. Firstly, due to the characteristics of intermittent connection, routing mechanism is one of the most important problems. Secondly, due to rising traffic congestion problem, the traditional fixed-time traffic lights system can’t satisfy the need of traffic control and reduce the efficiency in Vehiclular Delay Tolerant Network.In order to overcome these issues, this thesis proposes EERPP protocol. And applying DTN to intelligent transportation scenario, it also proposes VDNC algorithm and ATCG algorithm. ONE and MATLAB are used to carry out simulations. This thesis mainly includes the following three aspects.1) In order to improve energy efficiency, this thesis proposes an Energy-Efficient Routing Protocol based on Probability in DTN, where a node makes its routing decision according to the metric of the average energy consumption for a message arriving at the destination node.2) This thesis proposes a Vehicular Delay-tolerant Network routing algorithm based on Contention, which includes three strategies: the intersection selection strategy based on the Manhattan Distance and traffic information, the first competitive strategy based on the direction of movement and the second competitive strategy based on the position information. VDNC algorithm has a higher delivery rate and lower transmission delay.3) Taking environment protection and efficiency into account, this thesis proposes an Adaptive Traffic-light Control algorithm based on Green-Computing, which includes the calculation of the optimal sequence and that of the recommended speed. The branch and bound algorithm is used to calculate the optimal sequence and the calculation of the recommended speed is based on three phase modes to avoid switching the speed frequently.