Messaging Layer Security (MLS) is a security layer for encrypting messages in groups of size two to many. It is being built by the MLS working group and designed to be efficient, practical and secure. The proposed MLS specification is in two parts:

• an architecture document setting out the context, problem domain and security requirements, and
• a protocol document defining the protocol itself.

Official website:

• https://messaginglayersecurity.rocks/
• https://github.com/mlswg

MLS implementions:

• https://github.com/mlswg/mls-implementations/blob/main/implementation_list.md

Related projects:

• https://keytransparency.org/ [GitHub]

https://darkmail.info/ - Dark Mail Technical Alliance
https://autocrypt.org/ - Convenient End-to-End Encryption for E-Mail