A Secure Spectrum Handoff Mechanism in Cognitive Radio Networks

Cognitive Radio Networks support dynamic spectrum access by allowing unlicensed users to operate over temporarily idle licensed channels.Because primary users can reclaim spectrum unpredictably, secondary users must switch channels through spectrum handoff to avoid interference and sustain connectivity.Although many handoff approaches optimize delay and spectrum availability, security considerations are frequently overlooked, exposing CRNs to risks such as illegitimate PU impersonation, falsified sensing reports, and malicious handoff signaling exploitation.These weaknesses can trigger interference violations, session drops, and inefficient spectrum use.To address these concerns, this work presents a secure spectrum handoff solution that embeds user authentication, protected handoff control exchange, and intelligent channel selection.The scheme validates the authenticity of spectrum-holding PUs through a combined reputation and trust scoring model, while handoff coordination messages are secured using cryptographic protection to mitigate replay, spoofing, and signaling tampering.To balance performance and security, a forward-looking channel reservation module is used to reduce security-related handoff failures and preserve service quality.The method is analyzed using simulation metrics, including secure handoff success ratio, probability of deceptive handoff, spectrum efficiency, and control security cost.The evaluation confirms that the proposed approach strengthens handoff robustness in hostile spectrum scenarios while keeping delay and security overhead within practical limits for real CRN applications.