Tracing Faults in Mobile Ad Hoc Networks Using Symmetric Authentication Chains

Mobile Ad Hoc Networks (MANETs) are a collection of wireless mobile nodes with links that are made and broken arbitrarily. They have limited resources in power, computation, broadcast range, and a dynamic topology with no fixed infrastructure. Communication is accomplished by routes where individual nodes relay packets between a source and destination. A lot of work has been done in this area since 1998 focusing mainly on availability, reliability, or efficiency of routing algorithms. Little thought has gone into security as part of the protocol development process. In many instances, MANET security has been built-in as an afterthought. Before MANETs become a mainstay in computing applications, many security issues need to be addressed. One such issue is the insider threat. How does one find and effectively neutralize a malicious node? It has been recently shown how to do this with digital signatures; however, this may not always be possible because of the computational cost of digital signatures. CONTRIBUTION OF THESIS: The main contribution of this thesis is to present the following: • An approach for dealing with malicious faults in MANETs • A forward and reverse symmetric key authentication chain for MANETs • A malicious fault tracing algorithm for communication routing protocols in ad hoc networks with constrained resources