Cognitive Radio Network Security Threats: A Review

Overcrowded ISM band and inefficient spectrum utilization at a licensed band lead to the development of Cognitive Radio Network. It is an intelligent wireless technology capable of learning and adapting changes in surrounding environment parameters. However, the security of Cognitive radio restricts its widespread application. In addition to traditional wireless network security threats, cognitive radios are vulnerable to new threats posed by flexible spectrum allocation policy. Various attacks are targeting the physical, MAC, network, transport and application layers of a protocol stack. There is a need to have an excellent knowledge of the attacker's characteristics for secure and robust Cognitive Radio deployment. This paper meticulously recaps the security hazards posed to the cognitive radio network at various layers. Also, we have summarized attacks according to protocol layer and security requirements in a tabular format.