Convergence (SSL)

Convergence was a proposed strategy for replacing SSL certificate authorities, first put forth by Moxie Marlinspike in August 2011 while giving a talk titled "SSL and the Future of Authenticity" at the Black Hat security conference. It was demonstrated with a Firefox addon and a server-side notary daemon.

In the talk, Marlinspike proposed that all of the current problems with the certificate authority (CA) system could be reduced to a single missing property, which he called "trust agility" and which Convergence aimed to provide. The strategy claimed to be agile, secure, and distributed.

As of 2013, Marlinspike was focused on an IETF proposal called TACK, which was designed to be an uncontroversial first step that advocates for dynamic certificate pinning instead of full CA replacement and reduces the number of times a third party needs to be trusted.

Development of Convergence was continued in a "Convergence Extra" fork until about 2014.