Impact of Sharing Disruption in MC CR-NOMA

Spectrum sharing disruption in cognitive radio networks (CRNs) can significantly degrade network performance. Most sharing disruption attacks in the literature focus on orthogonal multiple access (OMA) or higher layers, such as medium access control (MAC). However, this paper focuses on multi-carrier cognitive radio non-orthogonal multiple access (MC CR-NOMA). The sharing disruption mechanism was established by jamming the channel estimation phase. This is shown to cause a denial-of-service (DoS) for secondary users. We derive the optimal power allocation to disrupt spectrum sharing for a number of secondary users. This is demonstrated by deriving the maximum average number of DoS bands under a constraint on power of the adversary. Furthermore, a comparison between optimal power allocation and uniform power allocation is provided. Both the analytical and numerical results of the optimal sharing disruption are presented. Overall, this study highlights the vulnerabilities in spectrum sharing for MC CR-NOMA and presents a new type of attack.