Active tapping scheme to wireless secret key generator employing Duplex Amplifying Repeater

This paper proposes an active tapping scheme to wireless secret key generator (WSKG), and evaluates tapping tolerance of WSKG for the active tapping scheme. An active tapping scheme is a tapping scheme in which the eavesdropper attacks user terminals actively. The proposal active tapping scheme amplifies a wavelet between two user terminals by DAR (Duplex Amplifying Repeater), and an amplified wavelet dominates RSSI profiles of user terminals. Eve intercepts the wavelet, and is able to estimate the RSSI profile. We simulated WSKG with the proposal active tapping scheme in a 2D rectangular room surrounded by concrete walls. The results indicated that the proposal scheme can get high correlation between user terminals' RSSI profiles and Eve's RSSI profile.