The gateway is the core component of the Internet of Things and industrial control systems.
The gateway is the role of the link. Up and down the host computer, computer / touch screen monitoring system, MES, data application software, database; below the lower machine, including PLC, sensors, embedded chips. The lower machines of different manufacturers often speak different languages. The language of Siemens is called ProfiBus, the language of Schneider is called Modbus, and the language of AB is called Ethernet IP. In the field of building automation, there is BACnet.
The gateway has to shoulder the heavy responsibility of communicating with the lower computer. Its basic function is translation, that is, protocol conversion.