In wireless networks, the transmission between legitimate users can be easily overheard by an eavesdropper for interception due to the broadcast nature of wireless medium, making the transmission highly vulnerable to eavesdropping attacks. Physical layer based security has increased exponentially over the last few years mainly due to the emergence of decentralized networks and the deployment of 5G and beyond wireless communication systems. Traditional methods of providing security in such networks are impractical due to the light computational abilities of some wireless devices(such as RFID tags, certain sensors etc.) or to the very large scale or loose organizational structure of some networks. Addressing these concerns, researchers at Drexel have now developed a novel physical layer based technique for securing wireless communications by means of preamble obfuscation.

Current security methods that rely on encryption and decryption techniques to secure a transmission, reveal the sending and receiving nodes to the intruder. But Drexel’s unique  technique secures the wireless communication channel through obfuscating the physical layer at the gate level logic by using unique keys that are generated individually at both the transmitter and the receiver nodes which are only known to them. These symmetric secret keys extracted on both ends of the communication channel are then used to successfully encrypt the packet preamble. The novel technique prevents intruders using standard compliant radio transceivers from performing narrow band reactive jamming and eavesdropping based attacks. The technique has been extensively tested on Drexel’s SDC testbed and results show that an intruder without the correct decryption key is unable to detect the wireless packet using standard wireless packet detectors.