Relay Selection Strategy Based On Social-Trust In Distributed Shared Networks

With the rapid development of mobile communication technology,people put forward higher demands for the transmission,storage and sharing of data information,which promotes the development of D2D(Device-to-Device,D2D)communication technology.D2 D technology is conducive to improving the overall performance of the network and improving user experience.However,the process of wireless communication is subject to the limitation of communication distance,and the wireless signal is also subject to the influence of channel fading and other interference.Similarly,D2 D technology also faces these problems.Therefore,the combination of D2 D technology and relay technology can effectively improve the overall performance of distributed network.The specific research contents are as follows:(1)Based on the existing relay selection technology,the social network attribute is introduced into D2 D multi-hop distributed network,and a single-hop relay selection scheme based on socialtrust model is proposed.The social network included the user's historical encounter time and encounter frequency,which are combined to build an indirect social trust model.The optimal relay device determined by this scheme can achieve reliable relay communication between users,and the simulation results show that compared with other relay schemes,the proposed scheme can achieve better performance gain in terms of system power consumption.(2)Aiming at the D2 D relay communication scenario where single hop and two hops coexist,an improved two-hop relay selection scheme is proposed.Firstly,the candidate relay set is selected according to physical distance constraints and social relationship constraints,and the candidate relay have to meet the minimum rate requirements predefined for quality of service at the same time.Then,according to the improved two-hop relay strategy,a set of corresponding relay links is formed,which contains all single-hop and two-hop relay links.By comparing the total power consumed by each link,a relay path that consumes the least total power is selected.Simulation results show that the performance of the improved two-hop relay strategy is better than that of the traditional two-hop relay strategy.(3)Aiming at D2 D multi-hop relay communication scenario,a multi-hop relay selection scheme based on Dijkstra algorithm is proposed.The solution derives the capacity expression based on the transmission model,and social relationship conditions and the communication distance restriction condition are usd to screen candidate relays preliminarily.According to the relevant theoretical knowledge of graph theory,a reasonable weight matrix is set up to transform the multi-hop relay problem into Dijkstra single source shortest path problem,so as to complete the whole multi-hop relay selection process.The simulation results show that the proposed scheme can effectively improve the system throughput,reduce the number of hops of relay selection,reduce the overall network load,and ensure the security of transmission information.