Impact of Selective Dropping Attacks on Network Coding Performance in DTNs and a Potential Mitigation Scheme

Some ad hoc network scenarios are characterized by frequent partitions and intermittent connectivity. A store-and-forward network architecture known as the disruption tolerant network (DTN) has been designed for such challenging network environments. To further improve the delivery performance, some researchers have proposed some network coding schemes for DTNs. However, not much papers discuss the security issues of network coding schemes in DTNs. In this paper, we first discuss some attacks that can be launched against network coding schemes in DTNs. Then, we focus on evaluating the impact of selective data dropping attacks on the delivery performance of a network coding scheme we design for DTN. Next, we describe a mitigation scheme that we design to overcome such attacks. Our mitigation scheme uses dynamic redundancy factor to generate more coded packets when a source notices performance degradation in the delivery performance. Via simulation studies, we show that our mitigation scheme is effective in restoring the performance degradation caused by the selective dropping attacks as long as alternate DTN paths exist for a source/destination pair.