Random channel hopping schemes for key agreement in wireless networks

Secure wireless communications typically rely on secret keys, which are hard to establish in a mobile setting without a key management infrastructure. In this paper, we propose a channel hopping protocol that lets two stations agree on a secret key over an open wireless channel and without use of any pre-existing key. It is secure against an adversary with typical consumer radio hardware that only allows receiving on a single (or a few) channel at a time. Theoretical analysis and simulation results indicate that this approach can generate a 128-bit key in 0.3 seconds. This is significantly faster than prior techniques that extract key material from the wireless channel.