Social Tie Based Cooperative Jamming:A Game Model In A Two-layer Network

With the widespread application of wireless network in real life and the rapid increase in the number of users,the research on security technology in wireless communication has attracted much attention.Node cooperation is an effective method to overcome the limitations of single-antenna systems and improve the communication security,but there are still some flaws.Existing cooperative jamming schemes usually focus on the single physical network and pay little attention to the impact of social characteristics on the willingness of the jammers to cooperate.The state of the jammers has limitations in the cooperative jamming game.The system overhead is large when the number of physical devices in the communication network increases and the location is different.Moreover,it is difficult to realize the benefits on the actual physical devices.In order to solve the above problems of cooperative jamming technology,the ultimate goal of this paper is to study the influence of social characteristics on the willingness of jammers to cooperate,to analyze the system benefits thought the holders of physical devices,and to reduce the time overhead of the communication system.Since social tie is a common and very important characteristic in social networks,this paper firstly proposes the cooperative jamming game based on social tie in a single physical communication network,and performs simulation experiments.Because cooperative jamming is mainly limited to the single physical communication network,this paper studies from two perspectives of social network and physical communication network.A new two-layer network model is proposed to promote efficient cooperation among jammers,which the upper-layer network overlays the lower-layer physical communication network.The upper-layer is a social network composed of users with diverse social ties and the lower-layer is a physical communication network composed of diverse physical devices held by the communicators in upper-layer network.The cooperation nodes selection problem in a two-layer network is transformed into a game,which is a super-modular and exists the pure strategy Nash equilibrium.And the TS-Algorithm is designed to calculate the value of secrecy outage probability when the NE is reached.Simulation experiments are conducted under different Cd and social ties.The effect of cooperative jamming in a two-layer network is compared with that of a single physical communication network.Following conclusions can be come to through experiments: the computational complexityof the two-layer network is reduced to 1/Cd and more time-efficient than the single layer network.The benefit of jammer increases when the social tie is enhanced.This means that,obtaining the benefits of system through the devices' holders not only solves the problem that the benefits on the actual physical devices is difficult to realize,but also reduces the time overhead of the communication system and improves the system's security performance.For solving the limitation of jammers' states in previous studies,the SIR spreading model is introduced into the upper-layer social network,which the individual has three states: susceptibility,infection and recovery.Analogous to the three states of the SIR spreading model,three states of jammers are set in this paper: probable participation,obligatory participation and non-participation.Each jammer's initial state is probable participation rather than certainly participate in the previous studies.Then,the problem of cooperative jamming based on social tie in the two-layer network is transformed into a game after considering SIR characteristic.The existence of supermodel performance and Nash equilibrium is verified.And the SIR-Algorithm is designed to calculate the secrecy outage probability when the NE is reached.Simulation experiments are carried out at different social ties and infection rates.The effects of cooperative jamming in a two-layer network with considering the SIR characteristics is compared with that of a two-layer network without considering the SIR characteristics.After considering the SIR characteristic,experiments show that the jammer would have more willingness to participate in cooperative jamming and value the secrecy performance more when the social tie is stronger with others.With the same social tie,the value of the secrecy outage probability is lower than the value when the SIR characteristic is not considered.This means that,it not only overcomes the limitations of jammers' states than the previous studies,but also promotes the cooperation willingness among the jammers.Moreover,our method increases the benefits of the jammers,and enhances the confidentiality of the communication system.