Secure spectrum sensing in CRNs: A study on SSDF attacks and countermeasure using USRP

In Cognitive Radio Networks (CRNs), the Medium Access Control (MAC) protocol is essential for managing dynamic spectrum access among secondary users (SUs) without disrupting primary users (PUs) transmissions. The MAC protocol’s decisions are based on the availability of spectrum bands determined through spectrum sensing (SS). To improve SS efficiency, SUs collaborate to detect unused spectrum bands more accurately, reducing false alarm rates and enhancing SS reliability. However, cooperative SS is vulnerable to Spectrum Sensing Data Falsification (SSDF) attacks, compromising SS integrity and affecting MAC protocol decisions. An ElGamal-based digital signature (EGDS) algorithm is used to authenticate SS information and protect against unauthorized access. Using digital signatures, SUs can securely authenticate spectrum access requests and messages, mitigating unauthorized access and tampering risks. The EGDS algorithm ensures the authenticity and integrity of communication between SUs and the spectrum access system. This approach detects modifications post-signature generation, maintaining SS reliability and enabling MAC protocols to make better decisions on token distribution and spectrum access in CRNs. Universal Software Radio Peripheral (USRP) devices are utilized to demonstrate SSDF attacks and showcase vulnerabilities and countermeasures.