Providing privacy for sensor networks is an important problem that is complicated by the fact that it is easy for adversaries to observe communications between sensor nodes. A first line of defense for protecting sensor communications is cryptography. However, these methods cannot address the complete spectrum of privacy issues in sensor systems. Specifically, security solutions are inadequate for protecting the privacy of contextual information surrounding a sensor application, such as the source's location, or the time at which a measurement was made, or even the size of sensor data packets.
This project investigates the development of a framework for providing three critical types of contextual privacy to sensor communications: source location privacy, temporal privacy, and traffic privacy. The project takes the viewpoint that the existing network stack can be modified to protect privacy while maintaining desirable levels of resource-efficiency. This investigation will enhance the privacy levels achieved through the development of new routing protocols involving the use of directed random walk techniques to obfuscate the data source, the modification of the structure of sensor messages to prevent traffic analysis attacks, the introduction of delay in the delivery of messages to reduce temporal correlation attacks, and the introduction of modifications to physical layer communications and the sensor topology to prevent the localization of a communication source. Through dissemination of the research results in both archival publications and new curricula, this project will advance the development of sensor applications by addressing critical privacy issues before sensor systems become a communal asset.
