Stochastic Geometry-based Comparison of Secrecy Enhancement Techniques in D2D Networks

TL;DR

This paper compares two secrecy enhancement techniques in D2D networks using stochastic geometry, deriving conditions under which each method is more effective in maintaining secure communications.

Contribution

It provides a stochastic geometry-based analysis of guard zones and artificial noise techniques, establishing thresholds for their effectiveness based on eavesdropper density.

Findings

Guard zone technique outperforms artificial noise at higher transmitter-receiver distances.

A threshold eavesdropper density determines when secrecy techniques are necessary.

Analytical expressions for secrecy outage and coverage probabilities are derived.

Abstract

This letter presents a performance comparison of two popular secrecy enhancement techniques in wireless networks: (i) creating guard zones by restricting transmissions of legitimate transmitters whenever any eavesdropper is detected in their vicinity, and (ii) adding artificial noise to the confidential messages to make it difficult for the eavesdroppers to decode them. Focusing on a noise-limited regime, we use tools from stochastic geometry to derive the secrecy outage probability at the eavesdroppers as well as the coverage probability at the legitimate users for both these techniques. Using these results, we derive a threshold on the density of the eavesdroppers below which no secrecy enhancing technique is required to ensure a target secrecy outage probability. For eavesdropper densities above this threshold, we concretely characterize the regimes in which each technique outperforms the other. Our results demonstrate that guard zone technique is better when the distances between the transmitters and their legitimate receivers are higher than a certain threshold.