Localization-based Secret Key Agreement for Wireless Network.

摘要

Due to the shared nature of wireless medium, generating secret key between legitimate nodes under the presence of eavesdroppers remains challenging in wireless network environment. In this research, a framework of secret key agreement utilizing observations of nodes relative location is considered. While many current works concern secret key generation only for 3-nodes (2 legitimate nodes and 1 eavesdropper), this research proposes an approach and analysis for a wireless network environment with m (m>3) legitimate nodes and 1 eavesdropper. The proposed algorithm uses the distance between a randomly selected node 1 and node 2 as the Reference Distance (RD) to establish the secret key. In order to secure the delivery of RD to other m-2 nodes, an Additive Distance Value (ADV) is used for public discussion. Further, different types of topologies are developed to accomplish secret key agreement for m node wireless network including star, chain and hybrid topologies. After the ADV distribution and RD estimation, the secret key is generated through secret bit extraction. The Maximum achievable Secret key generation Rate (MSR) based on the above network topologies is studied through theoretical analysis and mathematical estimation. Based on these analyze, the feasibility of proposed secret key generation algorithm is validated with a comparable secret key generation rate. The relationship between secret key, wireless network size and signal-noise ratio has been identified. Moreover, a comparison between star topology, chain topology and hybrid topology has been discussed. After that, several wireless network models including random patterned moving wireless nodes are studied to show the feasibility and performance of our proposed secret key generation algorithm. A chain topology improving method is proposed based on the wireless network model simulation. Last but not the lease, in order to reduce the bit mismatch rate, an optional secret key agreement procedure is also proposed. In all, this research studies the secret key agreement based on localization information in an m node wireless network under the presence of eavesdroppers.