Density-aware store-carry-forward routing with adaptive forwarding probability control

Store-carry-forward routing is a promising solution for achieving end-to-end delivery of messages in intermittently connected mobile ad-hoc networks. To reduce the number of message copies without increasing the message delivery delay, a probabilistic store-carry-forward routing scheme based on node density has been proposed so far. In this routing scheme, the forwarding probability is determined depending on node density and it is set to be small in high node-density areas. Although this routing scheme can suppress the speed of disseminating message copies over high node-density areas, the number of forwarded message copies increases gradually as time goes by. This means that a large delivery delay of a message causes excessively many copies to be disseminated. To solve this problem, we propose a routing scheme with an adaptive forwarding probability control, where the forwarding probability is reduced every time its copy is forwarded to a node. With simulation experiments, we evaluate the performance of our scheme in terms of the mean delivery delay and the mean number of forwarded message copies.