Coordination Without Collaboration in Imperfect Games: The Primary User Emulation Attack Example

In cognitive radio networks, an adversary transmits signals with characteristics that emulate those of primary users to prevent secondary users from transmitting. Such an attack is called a primary user emulation (PUE) attack. In this paper, a game theoretical framework is proposed to study the primary user emulation attack (PUEA) on cognitive radio nodes as a game of imperfect information between the secondary users (SUs), who do not exchange game information between them against the adversaries generating the PUEA and to define optimal strategies with minor computational demands. When the SU challenges the PU emulator successfully, updating the information on a cloud-based database enables the rest of the network to know the identity of PUE. As the game evolves, the grand coalition of the secondary users acts as the one without collaboration against the PU emulator playing a winning strategy. The performance of the game for optimal strategies is equal to the performance of the collaborative methods for PUEA detection.