Friendship-based cooperative jamming for secure communication in Poisson networks

This paper investigates the physical layer security-based secure communication in a finite Poisson network with social friendships among nodes, for which a social friendship-based cooperative jamming scheme is proposed. The jamming scheme consists of a Local Friendship Circle (LFC) and a Long-range Friendship Annulus (LFA), where all legitimate nodes in the LFC serve as jammers, but the legitimate nodes in the LFA are selected as jammers through three location-based policies. To understand both the security and reliability performances of the proposed scheme, we first derive analytical expressions for the transmission outage probability and determine both the upper and lower bounds on the secrecy outage probability, given the basic Laplace transform of the sum interference at any location in the network. With the help of the tools from stochastic geometry, we then provide general expressions for the above Laplace transform under all path loss scenarios as well as closed-form Laplace transform results under two typical path loss cases, such that the overall outage performances of the proposed scheme can be depicted. Finally, we present extensive numerical results to validate our theoretical analysis and also to illustrate the impacts of the friendship-based cooperative jamming on the network performances.