Location Related Routing In Delay Tolerant Networks

Delay tolerant network is a new concept in the field of wireless networks in recent years. It refers the wireless networks where nodes can only communication intermittently and even most of the time in interrupt status. Because there is no stable end to end transmission path in delay tolerant network, so the traditional network routing algorithm is no longer applicable to delay tolerant network. How to delivery data efficiently in delay tolerant network, that is delay tolerant network routing problem, is still a challenging and urgent problem and has important research significance. Therefore, we carried out the delay tolerant network routing algorithm research under the support of National Natural Science Foundation project in this paper.Existing delay tolerant network routing algorithms either based on the inefficient flooding strategies, or need to know the global contact probabilities of pair-wise nodes so that they are impractical to the real applications. We introduce the location information to the delay tolerant network routing algorithm, and propose location related unicast and multicast routing algorithm. With the guide of location information, it eliminate the blindness of routing based on flooding, making the route more purposeful and focused. it requires only local information, making the route algorithm more practical. We also compared the performance of the algorithm through simulation. The main research contents and innovations in this paper are as follows:1) we propose a location related delay tolerant network unicast routing algorithm-LRR. Compared to other unicast routing algorithms, LRR algorithm's greatest attribute is that: it turns the routing problem among mobile nodes into the routing problem among static locations by introducing the location information to DTN routing, and then selects the relay location and the corresponding forwarding nodes according to the probabilities of node's access to locations. As a result, LLR need not know global contact probabilities. Experimental results show that under the guidance of location information, LRR can improve the success delivery rate and reduce the delivery delay, and reduce the average packet forwarding number.2) we propose a location related delay tolerant network multicast routing algorithm–LRMR. On the one hand,it just need local information. On the other hand, in order to reducing the transport cost of packets, based on the initial partition of the destination node set, it merger the destination node subsets to increase the efficiency over cost metric in a greedy way, so it reduce the cost of multicast routing with no effect of the Performance of algorithm. Simulation results show that, LRMR algorithm can improve the success delivery rate of packets and reduce the average packet forwarding number.