A gateway for a fieldbus system for connecting a controller to an industrial plant having a plurality of different components. The gateway includes at least one component interface via which the different components can be connected simultaneously or sequentially, a control interface to which a controller of the industrial plant can be connected, and a data processing module which, when at least one of the components is connected to the at least one component interface, is configured to identify the at least one component on the basis of a hardware address assigned thereto and to communicate with the at least one component via the component interface, and which, when the controller is connected to the control interface, is configured to communicate with the controller and to represent the at least one component with respect to the controller as a function-based representation. Furthermore, a fieldbus system is described.