Free software for replacing Skype

The GNU Telephony secure calling project, built around GNU SIP Witch and the GNU ZRTP stack, offers the means for anyone to create and deploy network scalable and secure peer-to-peer VoIP collaboration solutions to enable privacy without the need for a central service provider, undocumented protocols, or proprietary software to achieve these goals. Our overall vision is to facilitate both solutions that are privately built, such as for organizations that wish to have secure communication as a foundation, and especially which can be autonomously assembled bottom-up directly by users over the public Internet as a full public alternative to Skype, using only free software and that depends purely on existing DNS for user lookup, rather than requiring a mediating service provider.