Layered Secrecy on Broadcast Networks

Date: 11:00am, September 12, 2017
Location: MUDD 1306 
Speaker: Shlomo Shamai, Professor, Technion 

Abstract: We review the setting of layered secrecy, addressing the degraded broadcast channel. The basic framework facilitates for a legitimate receiver who enjoys a better channel quality (channel state information, unavailable to the transmitter) to decode more secret messages, while the eavesdroppers with worse channel quality are kept ignorant of more messages.

While this layered based secrecy coding approach (variable-to-fixed rate secrecy coding) is evaluated for degraded channels, the strategy is relevant to general settings, though not necessarily optimal. Examples of the approach for fading channels, where the legitimate and eavesdropping channels are corrupted by multiplicative random fading gains are presented.

We use a similar paradigm of a layered approach to address secret sharing problem, where groups of users are able to determine certain secrets by sharing their channel outputs, and other groups of users are kept ignorant of certain secrets even if they share their outputs.

We also present secret capacity region results for secrecy outside of a bounded range, focusing on simple models, for which it is shown that the secret capacity requires combinations of superposition coding, binning, and embedded codes, as well as sharing designs (as rate splitting). Specific capacity results are demonstrated for the K-user degraded broadcast channel with a two level secrecy range. For this case an induction approach for the Fourier-Motzkin elimination is developed yielding the closed form capacity results. In the concluding outlook we discuss secret communication designs for different models.

Biography: Shlomo Shamai (Shitz) received the B.Sc., M.Sc., and Ph.D. degrees in electrical engineering from the Technion - Israel Institute of Technology, in 1975, 1981 and 1986 respectively. During 1975-1985 he was with the Communications Research Labs, in the capacity of a Senior Research Engineer. Since 1986 he is with the Department of Electrical Engineering, Technion - Israel Institute of Technology, where he is now a Technion Distinguished Professor, and holds the William Fondiller Chair of Telecommunications. His research interests encompasses a wide spectrum of topics in information theory and statistical communications.

Dr. Shamai (Shitz) is an IEEE Fellow, a member of the Israeli Academy of Sciences and Humanities and a foreign member of the US National Academy of Engineering. He is the recipient of the 2011 Claude E. Shannon Award and the 2014 Rothschild Prize in Mathematics/Computer Sciences and Engineering.

He has been awarded the 1999 van der Pol Gold Medal of the Union Radio Scientifique Internationale (URSI), and is a co-recipient of the 2000 IEEE Donald G. Fink Prize Paper Award, the 2003, and the 2004 joint IT/COM societies paper award, the 2007 IEEE Information Theory Society Paper Award, the 2009 European Commission FP7, Network of Excellence in Wireless COMmunications (NEWCOM++) Best Paper Award, and 2014 EURASIP Best Paper Award (for the EURASIP Journal on Wireless Communications and Networking). He is also the recipient of the 2010 Thomson Reuters Award for International Excellence in Scientific Research and is listed in the 2014 Thomson Reuters "The World's Most Influential Scientific Minds".' He is also the recipient of 1985 Alon Grant for distinguished young scientists and the 2000 Technion Henry Taub Prize for Excellence in Research. He has served on the Executive Editorial Board of the IEEE Transactions on Information Theory and has also served as a Shannon Theory Associate Editor for this journal. He has served twice on the Board of Governors of the Information Theory Society.

500 W. 120th St., Mudd 1310, New York, NY 10027    212-854-3105               
©2014 Columbia University