Any WSN node consists at least of a wireless transceiver with antenna, a microcontroller and memory, networking and application software and a power supply. The wireless transceiver with antenna is needed to receive and transmit data over the air. Selection of these components determines transmission range and strongly influences power consumption. A microcontroller and memory are used to process received data, to prepare data for transmission and to execute required networking and application specific tasks. It is also used to determine the power consumption and software limitations. Networking and application software specifies networking protocols and application functionality. Implemented networking features determine functional flexibility on the application level and the power supply is needed to power the device. A WSN node might include a sensor/actuator and other peripherals, but this is optional. A sensor/actuator is used to collect measurements or perform actions while other peripherals are application specific hardware (additional MCUs, connectors, etc.).