Secure device pairing using audio

Secure device pairing between mobile devices is a challenging task. The lack of a trusted authority and low computational power make it difficult for mobile devices to establish secure communication channels in ubiquitous computing environments. Solutions have been proposed using location limited channels to transmit secure pairing information that can be verified as originating from the intended device, enabling users to establish secure channels over insecure mediums. Of particular interest is using audio as a location-limited channel, due to the widespread deployment of audio capabilities on mobile devices. We describe a solution for secure device pairing using audio, called UbiSound, which only requires a single audio transmission to authenticate both devices. We describe our communication protocol, implementation details and results, and discuss how our solution is resistant to a number of attacks. Additionally, we emphasize how our solution is usable for visually impaired users.