Sensors can be programmed to take measurements, translate that data into signals, and then send that data to a main device called the controller. The controller is responsible for collecting data from sensors and providing an internet connection. Controllers may have the ability to make immediate decisions or they may send data to a more powerful computer for analysis. This more powerful computer might be in the same LAN as the controller or might only be accessible through an internet connection.
In order to reach the internet and then the more powerful computers in the data centre shown in the figure, the controller will first send data to a local router. This router interfaces between the local network and internet and can forward data between them..