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Planning device deployment is a fundamental issue in implementing wireless sensor network (WSN) applications. This design practice determines types, numbers and locations of devices in order to build a powerful and effective system using devices of limited energy supply and constrained capacities. The deployment plan decides the limits of many intrinsic properties of a WSN, such as coverage, connectivity, cost, and lifetime. In this thesis, we address the device deployment planning issues related to large-scale WSN systems. We consider a typical deployment planning scenario in a heterogeneous two-tier WSN composed of sensor nodes and relay nodes. Sensor nodes form the lower tier of the network and are responsible for providing satisfactory sensing coverage to the application. Relay nodes form the upper tier of the network and they are responsible for forwarding data from sensor nodes to the base station. As so, relay nodes should provide reliable connectivity to sensor nodes for an extended period of time. We therefore address the sensor node deployment in terms of the sensing coverage and relay node deployment in terms of the communication connectivity and system lifetime. For sensor node deployment, we propose a coverage-guaranteed sensor node deployment design technique. Using this technique, the sensing coverage is complete even if sensor nodes are randomly dispersed within a bounded range from its target locations according to a given grid pattern. In order to curb the increased cost due to extra sensor nodes that are used in the coverage-guaranteed deployment, while still maintaining a high-quality sensing coverage, we further study the probabilistic properties of the grid-based sensor node deployment in the presence of deployment errors. For relay node deployment, we propose to extend the system lifetime by distributing relay nodes according to a density function, which is optimized in response to the energy consumption rate, so that the energy is dissipated at an approximately same rate across the network. We further craft the deployment density function to reconcile the needs of balanced energy consumption and strong sensor node connectivity. The techniques proposed in this thesis fill the blank of available literature and can serve as guidelines for WSN designers, solution providers and system integrators of WSN applications. / Thesis (Ph.D, Electrical & Computer Engineering) -- Queen's University, 2008-01-15 09:33:53.917

Wireless sensor networks have applications in many places from wildlife environments to urban areas. Implementation of such a network is a challenging task because each specific application may require different constraints and objectives. To better meet the application requirements, cognitive wireless sensor network has been recently introduced. However, almost all the previous work in this area has been in theory or by simulation. Hence there is a demand to provide implementable ideas of cognition, implement, and analyze the results. The goal of this thesis is to implement a cognitive wireless sensor network with application in environment monitoring which is aware of the surrounding environment, updates its information based on the dynamic changes in the network status, makes appropriate decisions based on the gained awareness, and forwards required actions to involving nodes. An implementable cognitive idea is proposed based on the characteristics and goals of a cognitive system. Since transmission is one of the most power consuming processes in sensor nodes and non-efficient transmissions of data can lead to a shorter lifetime, this work tries to schedule nodes' transmission rate by the means of cognition and benefits from efficient scheduling of the redundant nodes to improve lifetime. To enhance a wireless sensor network with cognition, new nodes should be added to the architecture called cognitive nodes. Cognitive nodes will take care of most of the tasks in the cognition process while still there is a need to add a level of cognition to each individual node. The main contribution of this work is that it provides an implementable approach to cognition in wireless sensor networks, proposes a low complexity and low cost implementable idea for cognition, addresses implementation issues, and provides experimental results of different setups of the cognitive wireless sensor network. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2011-09-27 00:38:12.455

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.

Thesis (M. Phil.)--University of Hong Kong, 2010. / Includes bibliographical references (leaves 85-88). Also available in print.

Thesis (Ph.D.)--University of Texas at Dallas, 2009. / Includes vita. Includes bibliographical references (leaves 61-64)

Thesis (M.S.)--Rochester Institute of Technology, 2009. / Typescript. Includes bibliographical references (leaves 39-40).

Thesis supervisor: Ted Herman. Includes bibliographic references (p. 126-130).

Thesis (Ph. D.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 90-97). Also available on the World Wide Web.