The design of a defence mechanism to mitigate the spectrum sensing data falsification attack in cognitive radio ad hoc networks

Abstract

Cognitive radio networks (CRN) address the problem of spectrum scarcity by allowing unlicensed users known as secondary users (SUs) to utilize the unused spectrum band of licensed users known as primary users (PUs) without causing interference to the PUs. However, this results in some security challenges in which malicious SUs report incorrect spectrum observations. This attack is known as the spectrum sensing data falsification (SSDF) attack. In this paper, we investigate the SSDF attack in cognitive radio ad hoc network (CRAHN). We propose an integration of the reputation and the q-out-of-m rule schemes to mitigate the effects of the SSDF attack. The reputation based scheme and the time stamp of the last update of the reputation is used by the SU to determine the trustworthiness of its neighboring nodes based on their past reports. The q-out-of-m rule, in which the final transmission decision is informed by q sensing reports out of m nodes randomly polled. The integrated scheme is implemented in CRAHN where the presence of a data fusion Centre is not required. The proposed scheme is evaluated analytically.