University of Minnesota


DTC Seminar Series

Cryptographic Side-Channel Signaling and Authentication via Fingerprint Embedding


Brian M. Sadler
Army Research Laboratory
Adelphi, MD

Wednesday, October 17, 2018
3:30 p.m. reception
4:00 p.m. seminar

401/402 Walter Library

Brian M. Sadler

IEEE Distinguished Lecture Series

We describe a general framework for designing and embedding a fingerprint at the physical layer of a wireless network to achieve authentication with enhanced security and stealth. Fingerprint embedding is a key-aided process of superimposing a low-power tag to the primary message waveform for the purpose of authenticating the transmission. The tag is uniquely created from the message and key, and successful authentication is achieved when the correct tag is detected by the receiver. This enables control over performance trade-offs by design, and low-power fingerprints enhance security by making the authentication tags much less accessible to an adversary (Eve). Privacy analysis shows how Eve can be forced into difficult detection regimes, and secrecy analysis demonstrates that Eve’s uncertainty about the secret key is not readily reduced by an increase in her computational ability. In addition, the fingerprint embedding framework easily generalizes to create an authenticated communications side-channel for minimal cost. Side-channel information is conveyed to the receiver through the transmitter’s choice of tag from a secret codebook generated by the primary message and a shared secret key set. A linear coding scheme is introduced which enables tradeoffs among the performance goals of authentication, side-channel rate, secrecy, and privacy. Practical designs are readily achieved, and software-defined radio experiments validate the theory and demonstrate how the use of a set of secret keys for fingerprint embedding can, at minimal cost, allow secret and private side-channel communications, while simultaneously providing authentication with enhanced security.


Brian M. Sadler is an IEEE Signal Processing Society Distinguished Lecturer for 2017-2018. He is the Army Senior Scientist for Intelligent Systems at the Army Research Laboratory (ARL) in Adelphi, MD, is a Fellow of ARL, and a Fellow of the IEEE. He has been an associate or guest editor for a variety of journals including the IEEE Transactions on Signal Processing, EURASIP Signal Processing, IEEE SP Letters, IEEE SP Magazine, International Journal of Robotics Research, and Autonomous Robots. He received Best Paper Awards from the IEEE Signal Processing Society in 2006 and 2010, several ARL and Army R&D awards, and a 2008 Outstanding Invention of the Year Award from the University of Maryland. His research interests include information science, networked and autonomous systems, human-machine teaming, sensing, and mixed-signal integrated circuit architectures, and he has more than 400 publications in these areas with 14,000 citations and h-index of 51.

Contact Information

Digital Technology Center

499 Walter Library, 117 Pleasant Street SE, Minneapolis, MN 55455

P: (612) 624-9510

Connect on Social Media