| This dissertation presents the results of research that led to the development of a novel reputation and trust-based monitoring paradigm for secure and reliable computing in Wireless Sensor Networks (WSNs).;WSNs have undergone tremendous technological advances over the last few years. They have caused a giant leap toward "proactive computing," a paradigm where computers anticipate human needs and, when necessary, act on their behalf. Therefore, we cannot deploy such a critical technology without first addressing the security and privacy challenges to ensure that it does not turn against those whom it is meant to benefit.;The core application of WSNs is to detect and report events, be it military or civilian applications. The building blocks of a WSN are small, battery-powered, low-cost, self-contained devices called "sensors" that measure factors like light, temperature, pressure, vibration, motion, etc. A WSN usually consists of hundreds of thousands of sensors that operate in unattended, hostile territories to monitor a given geographical area. Once deployed, the wireless sensors self-organize into ad-hoc wireless networks in order to cope with the dynamics of the surveillance field. During the post deployment phase, the wireless sensors aggregate data, then process and generate a report, which is subsequently relayed from one sensor to the next using secure multi-hop routing until the data reaches its desired destination, which is usually the sink.;Since sensors operate in unattended and hostile territories, the adversary can capture a sensor node physically and extract all the information stored onboard, including cryptographic keying material. With this unique situation, WSNs are subject to a unique attack referred to as an "Insider Attack," in which the adversary becomes a legitimate member of the network being represented by the captured node. To overcome this unique situation, a distributed Reputation and Trust-based Monitoring System (RTMS) is required. The most critical contribution of this dissertation work has been the proposal and design of a novel, clique-based, distributed group-key establishment protocol with specific application to RTMSs. We have also proposed and evaluated the application of RTMS models for securing beacon-based localization in WSNs addressing information asymmetry attacks, and proposed a novel k-parent tree model for securing broadcast communication in WSNs with an underlying RTMS model. Other issues addressed in this dissertation work include the proposal of a Connected Dominating Set (CDS) based reputation dissemination and bootstrapping model. This model also enables secure, certificateless node mobility and enables the model to be robust to ID Spoofing and node replication attacks. |
