Anonymity and Privacy in Wireless Mobile Ad Hoc Networks

Abstract

Privacy has become a necessary property of networks as being considered as an important aspect of security by both network providers and customers. Privacy in general means to conceal one's personal information from others unless the ones who are allowed to access those information. Nowadays, many different services and applications are subject to privacy protection, e.g. in every day Internet usage for instance when the user registers with a website, protecting his personal information is critical while he may feel having nothing to hide. In ad hoc routing protocols, privacy becomes an important issue when mobile ad hoc networks enter security critical domains. In ad hoc networks due to the lack of a centralized support every device relying on other nodes for data transmission is responsible for its own routing operations and security issues. In this dissertation we present the methodology, design and the results of our research to achieve further steps toward private communication in ad hoc networks in hostile environments. Privacy in wireless environments is divided into two types: Identity anonymity and location privacy. Identity anonymity, as the main anonymity property, has attracted a lot of attention among researchers during the last decade. Identity anonymity has been addressed in many MANET (Mobile Ad hoc NETwork) routing protocols while location privacy is attracting an increasing attention and still needs appropriate solutions. Almost all of the existing works are designed to provide identity anonymity for MANETs rather than location privacy. In the routing protocols that provide identity anonymity, a strong enough traffic analyser could still track the nodes' locations in active routes. Privacy in ad hoc networks is a challenging issue due to the common vulnerabilities of wireless mobile networks. The attacker can launch traffic analysis against the routing information as well as eavesdropping the packets and tracing message flows in the network to discover their origin using an appropriate set of directional antennas. We believe that one of the important existing problems in the area of ad hoc network security is location privacy. Besides, although operating as groups is required by many ad hoc applications there is only a sparse work on anonymous multicast routing algorithms in the literature. Regarding the lack of appropriate anonymous multicast routing protocols for MANETS, we came up with the opinion that privacy in one-to-many communication is a challenge remaining to be solved in this kind of wireless networks. This thesis investigates solutions for network elements' anonymity and location privacy in unicast and multicast applications of MANETs. We propose a mechanism for destination location privacy in unicast ad hoc routing against a global eavesdropper as well as a framework for anonymous multicast routing for mobile ad hoc networks. We will provide both privacy analysis and implementation to evaluate the performance of our ideas. The evaluations demonstrate that the proposed techniques are successful in achieving the privacy goals while keeping the performance in a high level.