The traditional spectrum management techniques allow most of the spectrum to be used by licensed users exclusively. Spectrum sharing mechanism in Cognitive Radio Networks allows spectrum access to secondary user in addition to the primary licensed user. The Secondary Users, in order to compete for the spectrum, turn malicious and try to occupy all or a part of the available channel leading to Selfish Attacks. It results in a degradation of spectrum utilisation efficiency considerably. This paper presents a detection mechanism to counter the effect of selfish attack thereby aiming to improve the efficiency of spectrum utilization.

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Cognitive Radio Networks Spectrum Utilisation Selfish Attacks Spectrum Sharing Spectrum Sensing