Inter-contact delay and location information-based routing with adaptive threshold buffer management for delay tolerant networks

Abstract

Most of the routing algorithms in delay tolerant networks use multi-copy approach and messages stay for long time in the buffer because of no end-to-end connectivity between source to destination node. On one hand these activities ensure the high delivery probability, while on the other hand they introduce high resource overheads per message in the network. Therefore, limited storage capacity of buffer bound us to use intelligent message control buffer management policies. In this paper, we have proposed a combination of buffer management scheme for location information and inter-contact-based routing approach. The proposed buffer management scheme is a combination of message scheduling and message drop policy grounded on the concept of inter-contact delay based on delivery probability, hop count and number of copies of a message in the network. We also used adaptive threshold scheme which depends on average transferred bytes in the network to prioritise messages. It has been observed that our schemes results in reduction of overheads as compared to previous schemes. The probabilistic analysis of location dependent and independent encounters of nodes has been made to gain better insights of encounter timings. Experimental results obtained demonstrate the effectiveness of our proposed scheme.