Cognitive Spectrum and Its Security Issues

The current trend for opportunistic use of the licensed or licensed-exempt wireless spectrum with limited rules, or even without rules, introduces significant scientific and technical challenges for the networks of the future. Until now, for the realization of the cognitive radio paradigm, several spectrum sharing schemes have been proposed, such as centralized and distributed schemes, and cooperative or noncooperative spectrum sharing mechanisms. Unfortunately, some of the existing proposals for spectrum sharing and management introduce significant security leakages, putting into effect unfairness, unavailability, and selfishness, or even malicious behaviors. Additionally, the identification, recording and reporting of selfish, free-riders, malicious and anomalous actions by peers is still an open issue in the majority of the existing spectrum management schemes. This paper discusses and classifies the weak points and the vulnerabilities of the spectrum sharing mechanisms.