SReD: A Secure REputation-based Dynamic Window Scheme for disruption-tolerant networks

Disruption-tolerant networks (DTNs) provide a promising low-cost solution to transfer data in network environment where the connectivity is sporadic and unpredictable. Many existing methods for opportunistic data forwarding depend on the hypothesis that every node forwards messages regardless of the identities of the senders or receivers, however, the networks based on such methods are fragile under baleful attacks, such as black hole, denial of service (DoS), and wormhole. In this paper, we present a security strategy, namely SReD, to mitigate a number of known routing layer attacks. Our solution is a localized, link-state-based and multi-path routing protocol. We employ dynamic window mechanism to switch between reputation-based routing generation mode and probabilistic routing generation mode, and the proposed SReD is particularly suitable for resource-constrained DTNs. The proposed scheme has been compared with Epidemic and Prophet protocols in terms of efficiency and effectiveness against three common attacks. The results show that SReD is robust to these attacks and is more efficient under different metrics.