Exploiting Channel Diversity in Secret Key Generation from Multipath Fading Randomness

Abstract

We design and analyze a method to extract secret keys from the randomness inherent to wireless channels. We study a channel model for multipath wireless channel and exploit the channel diversity in generating secret key bits. We compare the key extraction methods based both on entire channel state information (CSI) and on single channel parameter such as the received signal strength indicators (RSSI). Due to the reduction in the degree-of-freedom when going from CSI to RSSI, the rate of key extraction based on CSI is far higher than that based on RSSI. This suggests that exploiting channel diversity and making CSI information available to higher layers would greatly benefit the secret key generation. We propose a key generation system based on low-density parity-check (LDPC) codes and describe the design and performance of two systems: one based on binary LDPC codes and the other (useful at higher signal-to-noise ratios) based on four-ary LDPC codes.

References in corpus (2)

• Using the Physical Layer for Wireless Authentication in Time-Variant Channels
• Key Generation Using External Source Excitation: Capacity, Reliability, and Secrecy Exponent

Cited by in corpus (5)

• Physical Layer Secret Key Generation in Static Environments
• Survey and Systematization of Secure Device Pairing
• Secret Key Agreement with Large Antenna Arrays under the Pilot Contamination Attack
• Design and Implementation of Secret Key Agreement for Platoon-based Vehicular Cyber-Physical Systems
• A Channel Perceiving Attack on Long-Range Key Generation and Its Countermeasure