Realization of the NAMUR diode by virtualization Secure separation using a hypervisor

NAMUR Open Architecture (NOA) aims to combine the benefits of the current automation systems, such as high availability, with the benefits of IT solutions in order to increase system flexibility without reducing security. For this purpose, it must be ensured that the information flow with the core process control does not affect the security requirements of the system. The term NAMUR diode indicates that the information flow is only allowed in one direction. In this paper, virtualization is proposed as a possible solution for separating core process control data from M+O servers and monitoring information flow between them.