The secunet SINA One Way Gateway 2 is a data diode that permits a data flow exclusively in one direction. The data can be transferred via the Gateway from an open or low-classified network to a higher-classified network without any need to change media. In this way, for instance, publicly accessible data can be processed further in networks that are classified or particularly worthy of protection. The unidirectional, physical connection between the networks is fully implemented in the hardware of the SINA One Way Gateway 2. This guarantees that data cannot flow in the opposite direction under any circumstances.