Delay and Physical Layer Security Tradeoff in Large Wireless Networks

Abstract

Exchange of crucial and confidential information in wireless networks leads to the unprecedented attention on the security problem. Though a number of works have studied the physical layer security, the joint optimization of the end-to-end delay management and the physical layer security, which requires a meticulous cross-layer design, has seldom been evaluated in the literature. In this work, by combining the tools from queueing theory and stochastic geometry, we analyze the tradeoff between delay and physical layer security in large wireless networks. Our numerical results reveal that the security performance is better for larger path loss exponent when the density of legitimate nodes is large, and it is reverse when the density is small. Meanwhile, it is observed that under the condition that a certain confidential rate is guaranteed, the delay performance is better in high signal-to-interference ratio regime than that in low SIR regime. In summary, this work provides an understanding and a rule-of-thumb for the practical design of wireless networks where both the delay and the security are key concerns.