Ph.D. Preliminary Exam - Chuang Wang

Date: 02 Nov, 2009
Time: 8:20 AM
Location: 223 Atanasoff Hall
Topic: Towards Achieving Privacy and Security in Resource Constrained Wireless Sensor Networks
Major Professor(s): Wensheng Zhang


Abstract:

Resource constrained wireless sensor networks have been widely deployed in many social settings to monitor human activities and urban environment. Accordingly, they will be interworked with other wireless networks, such as MANETs, VANETs, cellular networks, and so on, to provide ubiquitous and pervasive high performance wireless communications. However, sensor networks have inherent limitations: resource constraints, and security and privacy vulnerability. Extensive research therefore has been conducted to address these limitations by developing schemes to improve resource efficiency, enhance security, and preserve privacy. Unfortunately, these goals may not be easily achieved simultaneously and could even be sharply contrary to each other. Our research aims to reconcile the conflicts among these goals by studying how to achieve them simultaneously in several important contexts. Specifically, we investigate: (1) efficient, generic privacy preserving schemes for sensory data aggregation; (2) a privacy-preserving integrity detection scheme for sensory data aggregation; and (3) an efficient and source-privacy preserving scheme for catching packet droppers and modifiers.

To preserve data privacy for sensory data aggregation, we propose a set of generic, efficient and collusion-resilient privacy-preserving data aggregation schemes. Particularly, these include schemes to support data aggregation in queries targeted at special sensor data or the distribution of sensor data, and schemes to support queries targeted at particular sensor node. On top of the privacy preserving scheme, we develop a scheme to simultaneously achieve privacy and integrity attack detection for data aggregation. Our approach outperforms existing solutions in terms of generality, node compromise resilience and energy efficiency.

To thoroughly remove the negative effects caused by packet droppers and modifiers, we propose an efficient scheme to identify and catch compromised nodes which randomly drop packets and/or modify packets. Based on deliberate packet marking scheme, the privacy of packet source is preserved, and selective packet dropping and modifying are also alleviated. By dynamically changing the routing tree structure, most of the bad nodes can be identified through our node categorization algorithm and heuristic ranking algorithms with small false positive.

Extensive analysis and simulations have been conducted to evaluate the effectiveness and efficiency of our proposed schemes. The results show that our proposed schemes solve several limitations of existing work and achieve better performance in terms of resource efficiency, security strength and privacy preservation.