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Security vulnerabilities in IEEE 802.22

Cognitive Radio (CR) is seen as one of the enabling technologies for realizing a new spectrum access paradigm, viz. Opportunistic Spectrum Sharing (OSS). IEEE 802.22 is the world's first wireless standard based on CR technology. It defines the air interface for a wireless regional area network (WRAN) that uses fallow segments of the licensed (incumbent) TV broadcast bands. CR technology enables unlicensed (secondary) users in WRANs to utilize licensed spectrum bands on a non-interference basis to incumbent users. The coexistence between incumbent users and secondary users is referred to as incumbent coexistence. On the other hand, the coexistence between secondary users in different WRAN cells is referred to as self-coexistence. The 802.22 draft standard prescribes several mechanisms for addressing incumbent- and self-coexistence issues. In this paper, we describe how adversaries can exploit or undermine such mechanisms to degrade the performance of 802.22 WRANs and increase the likelihood of those networks interfering with incumbent networks. The standard includes a security sublayer to provide subscribers with privacy, authentication, and confidentiality. Our investigation, however, revealed that the security sublayer falls short of addressing all of the key security threats. We also discuss countermeasures that may be able to address those threats.