“Secure Wireless Communications: a Physical Layer Approach”

Abstract

Most of current secrecy approaches rely on the assumption that certain mathematical problems are difficult to solve and the opponent has limited computational power. With the development of advanced computational techniques, these assumptions will eventually become obsolete. At the same time, the broadcast nature of the wireless medium renders the channel more vulnerable to various security attacks, as compared with the wireline network. These factors motivate our attempt to develop information theoretically secure wireless  systems.

Our work adopts a new optimistic perspective in which the wireless medium is viewed as a resource instead of a liability. In particular, we identify three principles, namely opportunism, cooperation and feedback by which the wireless channel can be efficiently exploited to counter passive eavesdropping attacks. We propose several schemes that can achieve a non-zero rate between the primary source and destination while ensuring zero information leakage to the passive opponent. Using message authentication as an example, we also establish the utility of wireless medium in combating active attacks from the opponent.

Bio

Lifeng Lai received the PhD degree in Electrical and Computer Engineering from the Ohio State University in 2007. From March 2007, he has been working at Princeton University, first as a department guest then as a postdoc research associate. He was a Distinguished University Fellow of the Ohio State University from 2004 to 2007. His current research interest includes network information theory, wireless networks security and sequential analysis of wireless networks.