The main thing the Tox team is trying to do, besides provide encryption, is create a tool that requires no central servers whatsoever—not even ones that you would host yourself. It relies on the same technology that BitTorrent uses to provide direct connections between users, so there’s no central hub to snoop on or take down.
There are other developers trying to build a secure, peer-to-peer messaging systems, including Briar and Invisible.im, a project co-created by HD Moore, the creator of the popular security testing framework Metasploit. And there are other secure-centric voice calling apps, including those from Whisper Systems and Silent Circle, which encrypt calls made through the traditional telco infrastructure. But Tox is trying to roll both peer-to-peer and voice calling into one.
Actually, it’s going a bit further than that. Tox is actually just a protocol for encrypted peer-to-peer data transmission. “Tox is just a tunnel to another node that’s encrypted and secure,” says David Lohle, a spokesperson for the project. “What you want to send over that pipe is up to your imagination.” For example, one developer is building an e-mail replacement with the protocol, and Lohle says someone else is building an open source alternative to BitTorrent Sync.
Read More: http://www.wired.com/2014/09/tox/