PLS Analysis in an Indoor Heterogeneous VLC/RF Network Based on Known and Unknown CSI

In this article, we investigate the physical layer security in an indoor environment, wherein both visible light communication (VLC) as well as radio frequency (RF) technologies are codeployed. We explore the benefits of employing both technologies by imposing a limit of positive secrecy rate to prevent the eavesdropping attacks, which is an important metric in designing a secure wireless network. The VLC technology is used as a primary technology and the RF technology is used when the primary technology cannot satisfy the imposed limit. In particular, a novel secure-link selection mechanism is proposed to select the secure technology (i.e., either VLC or RF technology) based on the availability or nonavailability of instantaneous channel state information of both legitimate and eavesdropping links. The performance of the system is evaluated in terms of average secrecy capacity, connection outage probability, and secrecy outage probability. We observe the effect of various physical parameters on the security performance of the network. Further, analytical results are corroborated with the computer simulation results.