Minimizing Secrecy Outage Probability in Multiuser Wireless Systems With Stochastic Traffic

Abstract

We first extend the definition of the secrecy outage probability to wireless systems with adaptive transmission rates and secrecy rates. Then, we consider a scheduling problem in the aforementioned system, jointly considering the reliability, security, and stability, where the scheduler tries to allocate wireless resources to the legitimate users, stabilize the system, and minimize the secrecy outage probability. A stochastic network optimization framework is used to decompose the problem, and an online algorithm is proposed. We further consider a related problem, discuss the optimal solution, and show that the proposed algorithm cannot lead to optimal solution in some scenarios. By comparing the offline algorithm with our first algorithm, we further propose a second refined online algorithm, which is an optimal one. Extensive simulations are conducted to show the impact of the information arrival rate and the channel conditions on the system secrecy outage probability. These observations provide important insights and guidelines for the design and resource management of future wireless networks using secure communication technologies.