Ratcheting Trees and Building A Secure Messaging Platform
Ratchets only go forward, and never back.
We live in a flawed world of cybersecurity, and we often do not build systems that integrate all the most important features for privacy and trust. That, though, is changing, and when, in 2016, representatives from Cisco, Mozilla and Wire Swiss GmbH met at a meeting at IETF 96 in Berlin. The focus of the meeting was to use pairing-based cryptography to integrate with end-to-end encryption and group communications.
While many existing methods struggled with scaling, a new paper then appeared in 2017 that introduced the concept of Asynchronous Ratcheting Trees [here][1]:
This method has since developed into the TreeKEM approach.
Double Ratchets
The Asynchronous Ratcheting Trees paper outlined a way to create efficient encryption for secure group communications. Other ratcheting methods do exist, such as with the Double Ratchet method, and which was Trevor Perrin and Moxie Marlinspike, and is used in Open Whisper Systems Signal package.
