Whonix is an operating system focused on anonymity, privacy and security. It's based on the Tor anonymity network[1], Debian GNU/Linux[2] and security by isolation. DNS leaks are impossible, and not even malware with root privileges can find out the user's real IP.
Whonix consists of two parts: One solely runs Tor and acts as a gateway, which we call Whonix-Gateway. The other, which we call Whonix-Workstation, is on a completely isolated network. Only connections through Tor are possible.
License : Open Source
https://www.whonix.org/wiki/Main_Page
