Wireless Secret Key Generation And Security Analysis

With the rapid development of mobile Internet services, information security for wireless communication is becoming a very important research topic. Traditional secret key sharing procedure relies on computational hardness which would be facing serious challenge with the development of computer. Recently, there has been great interest in generating the shared secret key based on the physical layer security techniques, which exploits the wireless channel to generate secret key and could achieve the perfect secrecy combined with a one-time pad. In this paper, we introduce the physical layer security techniques, mainly focus on the following aspects:(1) Practical quantization algorithms include two simple methods: Channel Quantization with Guardband(CQG) and Channel Quantization Alternating(CQA). One challenge associated with the approaches is that it tends to suffer from high probability of disagreement for the bits generated at the two nodes. We extend CQA for channel quantization to improve the resulting key agreement. The methods are simulated and their performance is compared in terms of efficiency and the mismatch rate of key bits.(2) The Cascade information reconciliation protocol is simple and probably the most widely used in QKD(Quantum Key Distribution) implementations or physical layer security. Cascade is highly interactive, however, which makes it very sensitive to network latencies. It is commonly believed that the interaction in cascade causes low throughput. We proposed a improved approach to reduce the number of interactive communication;(3) The iJam scheme is a novel physical-layer approach for secret key generation, where the generation of secret bits can be very fast and essentially independent of channel variations. In order to crack iJam scheme completely, we propose a double-eavesdroppers cooperative attack, which can be well employed to crack the iJam scheme. Extensive simulation results validate our claim.