A computer network has ports connected to production machines (PM) and communicating with an assigned virtual user interface and a higher-ranking facility located outside the PM. Connection of an additional PM is monitored, in which case a commissioning service automatically assigns a virtual user interface to the additional PM, re-initializes an individual virtual computer network within the computer network and connects the additional PM to the virtual user interface via the re-initialized virtual computer network. Communication between the additional PM and the assigned virtual user interface is isolated from other communications until, a release command is specified. A then activated integration service automatically re-initializes a virtual router for connection to the additional PM via the virtual computer network and configures the re-initialized virtual router such that the additional PM communicates with the higher-ranking facility via the re-initialized virtual router.