Systems in Adversarial Networks

Virtual coordinate systems provide an accurate and efficient service that allows hosts on the Internet to determine the latency to arbitrary hosts without actively monitoring all nodes in the network. Many of the proposed virtual co-ordinate systems were designed with the assumption that all of the nodes in the system are altruistic. However, this assumption may be violated by compromised nodes acting maliciously to degrade the accuracy of the coordinate sys-tem. As numerous peer-to-peer applications rely on virtual coordinate systems to achieve good performance, it is criti-cal to address the security of such systems. In this work, we demonstrate the vulnerability of decen-tralized virtual coordinate systems to insider (or Byzantine) attacks. We propose techniques to make the coordinate as-signment robust to malicious attackers without increasing the communication cost. We demonstrate the attacks and mitigation techniques in the context of a well-known dis-tributed virtual coordinate system using simulations based on three representative, real-life Internet topologies of hosts and corresponding round trip times (RTT). 1