Probability-based adaptive message transmission algorithm for opportunistic networks

Opportunistic networks is a special kind of mobile ad hoc networks in which communication opportunities are brought by node mobility spontaneously and temporally. Aiming at improving the current multi-copy routing algorithms in opportunistic networks, this paper firstly analyzes the weakness of the traditional multi-copy routing algorithms, such as high delivery delay, poor adaptivity to the different network environments. And then a Probability-based Adaptive Message Transmission Algorithm for Opportunistic Networks (PAMTA) was proposed to solve these problems. According to the level of connectivity of the network, PAMTA introduces the meeting probability between different mobile nodes. In order to enable routing algorithm to adapt to different network environments, PAMTA can adjust the number of message copies and message forwarding threshold adaptively. Simulation results show that PAMTA can achieve satisfying message delivery rate in opportunistic networks and reduces the message forwarding times by about 21.3% compared with Spray and Focus algorithm.