multiOTP is an open source PHP class, a command line tool, and a web interface that can be used to provide an operating-system-independent, strong authentication system.

If the strong authentication needs to be done from a hardware device instead of an Internet application, a request will go through a RADIUS server which will call the multiOTP command line tool.

For Windows, the multiOTP library is provided with a pre-configured RADIUS server (freeradius) which can be installed as a service.

Under Linux, the readme.txt file provided with the library indicates what should be done in order to configure the RADIUS server and the web service.

All necessary files and instructions are also provided to make a strong authentication device using a Raspberry Pi nano-computer.