Research On Physical-layer Identity Authentication In Wireless Networks

With the rapid advancement of wireless communication technology and ever-increasing mobile applications, securing wireless communication becomes prettyimportant and challenging. Compared to wired network, ensuring security in wirelessnetworks faces greater challenges mainly due to its broadcasting nature since an attackercan easily eavesdrop or intercept the wireless communication channel. Among the varioustypes of attacks in wireless networks, identity-based attacks are easy to launch and cansignificantly degrade network performance. Therefore, it is a critical issue that whether alegitimate user could authenticate the identity of another user who is involved in thecommunication accurately or not in wireless networks. Besides, there is a new trend thatmany researchers are trying to solve this security problem on physical layer recently.The unique properties of wireless physical layer which include the uniqueness,randomness, location-difference features of the wireless fading channel, as well as channelreciprocity, can be exploited to enhance the wireless network security. This paper proposesa novel physical layer challenge-response authentication mechanism for wireless networks.It fully utilizes aforementioned properties of wireless physical layer, and it adopts OFDM,which is widely applied in many modern wireless network standards, as its physical-layercommunication technique. In the authentication procedure, challenge-response signals areexchanged at the physical layer, which allow two users to verify their shared identity-authentication information while not revealing this information to attackers. Theinformation is masked by a random number and the channel fading, while the verifier isable to verify the information owing to a reverse operation in the response signal andchannel reciprocity.This paper conducts extensive simulation study under several different channelmodels for the proposed identity authentication mechanism, and develops a prototypeusing SORA to evaluate the mechanism in real-world environments. Both the simulationand real-world experiment results show that the proposed mechanism achieves both lowFAR and FRR in various channel conditions and under attack. Therefore, this work haslaid a solid foundation for physical layer authentication in wireless networks and the studyof wireless security.