容忍延迟网络(DTN)为提高消息传输成功率,往往采用多副本策略,导致网络消息泛洪现象,需要对消息副本进行限制。提出了一种基于社会活性和副本限制的DTN路由算法(social activity and copy-limited based DTN routing algorithm,SACRA),该算法基于节点运动历史轨迹和相邻节点特性定义社会活性,根据社会活性和可用缓冲区大小合理分配相遇节点携带消息的份额和交换消息类型,使消息加速扩散,能尽快到达目标节点。仿真结果表明,与典型的多副本DTN路由算法相比,SACRA能够有效降低了消息转发数和负载比率,当时间在1 000 s后成功率在50%以上,从而降低了网络开销,并获得较高的消息递交成功率。
Delay-tolerant networks (DTN) often use the copies of message to improve the success rate of message transmission.It can deduce the flooding of the messages in the network.So, the copies of message need to be limited.A social activity and copy-limited based DTN routing algorithm (SACRA) is proposed.The algorithm defines the social activity based on the historical track and the movement characteristic of adjacent nodes.According to the social activity and the size of the unused buffer, the number of message copies and the exchange type of its carrying messages are distributed in a reasonable way.The message can be diffused across the network and carried to its destination node quickly.The simulation results show that SACRA can reduce the network load effectively while retain the message delivery ratio well.When the time is 1 000 s, the success rate is above 50%, and thus the network overhead is reduced and the success ratio of the message delivery is increased compared with other typical routing algorithms.