A framework for anonymous routing in delay tolerant networks

Security and privacy issues are considered to be two of the most significant concerns to organizations and individuals using mobile applications. In this paper, we seek to address anonymous communications in delay tolerant networks (DTNs). While many different anonymous routing protocols have been proposed for ad hoc networks, to the best of our knowledge, only variants of onion-based routing have been tailored for DTNs. Since each type of anonymous routing protocol has its advantages and drawbacks, there is no single anonymous routing protocol for DTNs that can adapt to the different levels of security requirements. In this paper, we first design a set of anonymous routing protocols for DTNs, called anonymous Epidemic and zone-based anonymous routing, based on the original anonymous routing protocols for ad hoc networks. Then, we propose a framework of anonymous routing (FAR) for DTNs, which subsumes all the aforementioned protocols. By tuning its parameters, the proposed FAR is able to outperform onion-based, anonymous Epidemic, and zone-based routing. In addition, numerical analyses for the traceable rate and node anonymity models are built. Extensive simulations using randomly generated graphs as well as real traces are conducted to demonstrate that given appropriate parameter settings, our FAR outperforms all the existing anonymous routing protocols for DTNs.