Security in Diffusive Molecular Timing Channels: An Amount of Confusion Level Perspective

Abstract

Secure transmission of information to a desired receiver is an important attribute of any molecular communication system. This paper analyzes the secrecy performance for a multi-particle diffusive molecular timing channel. We first obtain the fractional equivocation and then employ three standard secrecy performance metrics, namely, generalized secrecy outage probability, average fractional equivocation, and average information leakage rate to evaluate the secrecy performance of the channel in the presence of an eavesdropping user. We then propose a new secrecy performance metric, the amount of confusion level, which quantifies the severity of the confusion level at the eavesdropping user. Compared to the aforementioned metrics which are mainly based on the first-order statistics, the amount of confusion level is a second order measure that characterizes the eavesdropping effect in a better way, especially in environments with very small value of the Lévy noise parameter. The dependence of various secrecy metrics on various physical parameters, especially the Lévy noise parameter and the degradation rate of information molecules, is studied. Our analysis suggests that an increase in the value of each of these parameters results in an improvement in the secrecy performance. Numerical results corroborate the derived analytical findings. © 2015 IEEE.