An Improvement of Security Scheme for Radio Environment Map Under Massive Attacking

Radio environment maps (REM) are widely used to enhance communication efficiency in spatial spectrum sharing. This can be generated using reports from the terminals. However, an open characteristic environment always leads to a security problem; for example, when malicious terminals exist in the environment and data falsification attacks occur, the accuracy of the REM is affected by the malicious action. In this study, we improve the double-layer monitor algorithm by optimizing the reward penalty function using a similarity comparison and sustainable monitor. The proposed algorithm can remove malicious terminal reports from the database to improve accuracy. Additionally, we propose a new algorithm involving interpolation based on spatial information to solve the problem of unequal information obtained from the meshes. By interpolation, a database can obtain sufficient datasets from each mesh. Furthermore, we defined an optimal attack strategy using the proposed security algorithm. The influence of malicious terminals can be the strongest among data falsification attacks; thus, we can check the performance more comprehensively. The simulation results indicate that the proposed method can eliminate the influence of malicious terminals and that a highly accurate REM can be obtained under massive malicious terminal attacks.