Dynamic Wireless Security
Wireless communication is a favorable environment for the idea of dynamic secrets due to its random nature. Noises, interferences, and many other random factors in wireless signal transmissions are natural sources of true randomness to be harvested by users. On the other hand, these random factors produce unavoidable decoding errors and information losses for the adversary. This chapter takes wireless LAN as an example to demonstrate a simple implementation of the idea of dynamic secrets in a practical secure communication system. Interestingly, the standardized link layer retransmission protocol of the wireless LAN allows a highly efficient implementation for dynamic secrets. Alice and Bob can synchronize their key updates without consuming any bandwidth. We demonstrate the implementation in a series of proof-of-concept experiments in an office wireless LAN environment. The implementation cost and the security performance of dynamic secrets are measured and discussed. The experimental results are quite encouraging and suggest a new way to deploy and operate a secure office wireless LAN.