Cognitive radio network security status and challenges

One of the important trends which is supposed to have more attention in the system of cognitive radio is wireless security models. Security requirements for CRNs are the same as the general wireless networks, taking into consideration that the frequency band changes dynamically adding a specific feature when we deal with security of CRNs. A new category of security issues and challenges have been introduced in the cognitive radio systems, and providing security models to realize good and reasonable protection must be one of the main researchers interest. This paper addresses the literature review, the security models and requirements for CRNs, layered and cross-layers attacks against CRNs.