This project refers to an Arduino sketch that implements a true random number generator with the help of an audio sensor. The sensor measures the sound volume in the nearby environment. The Arduino acts as a network device with an appropriate WEB interface in it from which we can access the random numbers. This technology is not new as it exists in other network devices. For example, routers or network printers have a WEB interface.
The WEB interface is installed in the Arduino itself and is supported with the help of a simple but quite progressive web server (which is also located within the Arduino). The Arduino is connected to the Internet with a special Ethernet card (Ethernet Shield). The Ethernet card is assigned with a static IP (because the Arduino in this case does not work as a client but as a server since the web server is executed there at port 80).
To enable the sound sensor to collect really random values as regards the volume of sound in the environment, it helps to place it in a noisy room or near a radio.
Efstathios Chatzikyriakidis 