Researchers send secure passwords through a human body

Computer scientists and engineers at the University of Washington have come up with a novel way to send passwords securely with no risk of being intercepted and hacked by eavesdroppers. The potential for passwords to be stolen and hacked when sent over WiFi or Bluetooth is very real and lots of research time and money is spent looking for more effective and secure methods. The UW team believes they have found a secure way of sending passwords through the human body.

The passwords are sent through the body using low-frequency transmissions generated by fingerprint sensors and touchpads on consumer devices. "Fingerprint sensors have so far been used as an input device. What is cool is that we've shown for the first time that fingerprint sensors can be re-purposed to send out information that is confined to the body," said senior author Shyam Gollakota, UW assistant professor of computer science and engineering.

The so-called on-body transmissions offer a much more secure way to transmit authenticating information between devices that are touched by a human body. The system could create a very secure link between anything your body touches such as smart doors, wearable medical devices, and lots more. The tech created by the UW team takes advantage of signals already generated by fingerprint sensors common on smartphones today and generated by the touchpads on laptops.

"Let's say I want to open a door using an electronic smart lock," said co-lead author Mehrdad Hessar, a UW electrical engineering doctoral student. "I can touch the doorknob and touch the fingerprint sensor on my phone and transmit my secret credentials through my body to open the door, without leaking that personal information over the air."

The team has so far tested this new technique using fingerprint sensors on the iPhone and other devices. In tests with ten different subjects of different weight and heights, the technique has worked. The system works when the users are in motion and when their arms are moving. The process creates the on and off basics of binary code to encode and transmit data and so far bit rates of 50 bits per second have been achieved with touchpads and 25 bits per second with fingerprint sensors.