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Communication in a sensor network needs guaranteed reception of data without fail and providing security to it. The authenticity and confidentiality of the data has to be ensured as sensors have limited hardware resources as well as the bandwidth. This thesis addresses the security aspects in wireless sensor networks. The main task of the project is to identify the critical security parameters for these distributed embedded systems. The sensors have extremely limited resources: small amount of memory, low computation capability and poor bandwidth. For example, a sensor platform can have 8KB of flash memory, a 4MHz 8-bit Atmel processor, and a 900MHz radio interface. Various security threats posed to these small wireless sensor networks has been made and solutions proposed. Secure communication between these communicating partners is to be achieved using cryptography.

Automated devices enabled by wireless communications are deployed for a variety of purposes. As they become more ubiquitous, their interaction becomes increasingly important for coexistence when sharing a scarce resource, and for leveraging potential cooperation to achieve larger design goals. This thesis investigates the use of game theory as a tool for design and analysis of networked systems of automated devices in the areas of naval defence, wireless environmental monitoring through sensor networks, and cognitive radio wireless communications. In the first part, decentralized operation of naval platforms deploying electronic countermeasures against missile threats is studied. The problem is formulated as a stochastic game in which platforms independently plan and execute dynamic strategies to defeat threats in two situations: where coordination is impossible due to lack of communications, and where platforms hold different objectives but can coordinate, according to the military doctrine of Network Enabled Operations. The result is a flexible, robust model for missile deflection for advanced naval groups. Next, the problem of cooperative environmental monitoring and communication in energy-constrained wireless sensor networks is considered from a game-theoretic perspective. This leads to novel protocols in which sensors cooperatively trade off performance with energy consumption with low communication and complexity overhead. Two key results are an on-line adaptive learning algorithm for tracking the correlated equilibrium set of a slowly varying sensor deployment game, and an analysis of the equilibrium properties of threshold policies in a game with noisy, correlated measurements. Finally, the problem of dynamic spectrum access for systems of cognitive radios is considered. A game theoretic formulation leads to a scheme for competitive bandwidth allocation which respects radios' individual interests while enforcing fairness between users. An on-line adaptive learning scheme is again proposed for negotiating fair, equilibrium resource allocations, while dynamically adjusting to changing conditions.

Over-the-air reprogramming is an important aspect of managing large wireless sensor networks. However, reprogramming deployed sensor networks poses significant challenges due to the energy, processing power and memory limitation of sensor nodes. For improved energy efficiency, a reprogramming mechanism should use less transmission and flash writing overhead. Past research has proposed different mechanisms for reprogramming deployed sensor networks. However, all of these mechanisms produce large patches if software modifications involve changing program layouts and shifting global variables. In addition, existing mechanisms use large amounts of external flash and rewrite entire internal flash. In this thesis, we present a differential reprogramming mechanism called QDiff that mitigates the effects of program layout modifications and retains maximum similarity between old and new software using a clone detection mechanism. Moreover, QDiff organizes the global variables in a novel way that eliminates the effect of variable shifting. Our experiments show that QDiff requires near-zero external flash, and significantly lower internal flash rewriting and transmission overhead than leading existing differential reprogramming mechanisms. / Thesis (Master, Computing) -- Queen's University, 2011-11-29 14:11:44.138

As the demand for cheaper electronic devices has increased, the location of manufacturing foundries has changed to untrusted places outside of the United States. Some of these locations have limited oversight of the manufacturing of complicated and sensitive electronic components including integrated circuits (IC). IC, a key component in all current electronic devices, can be modified to be malicious or to monitor the functions of their applications. These malicious modifications are called Hardware Trojans. Hardware Trojans can be de- signed to quietly monitor, to actively send out unencrypted sensitive information, or to actively destroy their host device. Our research demonstrates the ability of Hardware Trojans to infiltrate a sensor network that could be remotely deployed for various applications. This research is important due to the dearth of knowledge on the subject. Currently, software security is given great importance. Our research shows that the same level of importance must be given to hardware to ensure a trusted and secure environment.

This thesis addresses the performance evaluation and enhancement of wireless networks. Part I investigates the problem of resource allocation in cellular networks, focusing on handoff, and Part II investigates resource allocation in sensor networks focusing on power management. (For complete abstract open document)

Thesis (Ph.D.)--University of Nebraska-Lincoln, 2007. / Title from title screen (site viewed Dec. 4, 2007). PDF text: xvi, 266 p. : ill. ; 12 Mb. UMI publication number: AAT 3271934. Includes bibliographical references. Also available in microfilm and microfiche formats.

Thesis (M.S. in Electrical Engineering)--Vanderbilt University, May 2008. / Title from title screen. Includes bibliographical references.

Thesis (Ph.D.)--University of Nebraska-Lincoln, 2007. / Title from title screen (site viewed Mar. 27, 2008). PDF text: 188 p. : ill. ; 825 K. UMI publication number: AAT 3277703. Includes bibliographical references. Also available in microfilm and microfiche formats.

Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2008. / Includes bibliographical references (leaves 122-135). Also available in electronic version.