A cross-layer approach to enhance the security of wireless networks based on MIMO

The wireless networks lack a physical boundary due to the broadcasting nature of wireless transmissions. The security has become a critical concern in the physical layer of the wireless networks. In this paper, we propose a novel MIMO-aided security scheme. By exploiting an extra dimension provided by MIMO systems for adding artificial noise to the transmission process, which let the attacker´s signal be a degraded version of the legitimate receiver´s signal, the physical-layer security is enhanced as a result. In the proposed scheme the physical-layer may rely on upper-layer encryption techniques for security, which results in a cross-layer security scheme. The control sequence in the upper-layer can use some known stream ciphers. Finally, we gave the comparison of our scheme and the traditional cryptographic system. Our scheme can provide stronger security for wireless networks.