This article aims to provide a comprehensive overview on PHY layer security assisted ICV networks. Beginning with a discussion from a general perspective of the ICV network architecture, this work summarizes the major security threats faced by ICV networks. To achieve confidential data transmission with a low latency and a high data rate, several physical layer security schemes are surveyed in this article, which include RRM, cooperative jamming, multi-antenna technologies, and PHY-layer key generation. In addition, the performances of the aforementioned schemes are compared in terms of different aspects, followed by a discussion on some major challenges that need to be tackled in the implementation of ICV networks.