Messaging Layer Security

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Messaging Layer Security (MLS) is a security layer for end-to-end encrypting messages in arbitrarily sized groups. It is maintained by the MLS working group of the Internet Engineering Task Force to provide an efficient and practical security mechanism. [1] [2] [3]

Contents

Security properties

Security properties of MLS include message confidentiality, message integrity and authentication, membership authentication, asynchronicity, forward secrecy, post-compromise security, and scalability. [4]

History

The idea was born in 2016 and first discussed in an unofficial meeting during IETF 96 in Berlin with attendees from Wire, Mozilla and Cisco. [5]

Initial ideas were based on pairwise encryption for secure 1:1 and group communication. In 2017, an academic paper introducing Asynchronous Ratcheting Trees was published by the University of Oxford and Facebook setting the focus on more efficient encryption schemes. [6]

The first BoF took place in February 2018 at IETF 101 in London. The founding members are Mozilla, Facebook, Wire, Google, Twitter, University of Oxford, and INRIA. [7]

As of March 29, 2023, the IETF has approved publication of Messaging Layer Security (MLS) as a new standard. [8] It was officially published on July 19, 2023. [9] [10]

Implementations

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References

  1. "Inside MLS, the New Protocol for Secure Enterprise Messaging". Dark Reading. 27 June 2019. Retrieved 2019-11-15.
  2. at 10:29, Richard Chirgwin 22 Aug 2018. "Elders of internet hash out standards to grant encrypted message security for world+dog". www.theregister.co.uk. Retrieved 2019-11-15.{{cite web}}: CS1 maint: numeric names: authors list (link)
  3. "Messaging Layer Security". GitHub.
  4. "Messaging Layer Security (mls) -". datatracker.ietf.org. Retrieved 2019-03-05.
  5. "Das sind die sieben Entwickler-Trends 2019: Vom Java-Comeback über MLS bis KI/ML-zentrierte Technologien". IT Finanzmagazin. 2 January 2019. Retrieved 7 January 2019.
  6. Cohn-Gordon, Katriel; Cremers, Cas; Garratt, Luke; Millican, Jon; Milner, Kevin (2017). "On Ends-to-Ends Encryption: Asynchronous Group Messaging with Strong Security Guarantees". Cryptology ePrint Archive.
  7. Chirgwin, Richard (22 August 2018). "Elders of internet hash out standards to grant encrypted message security for world+dog" . Retrieved 30 November 2018.
  8. Sullivan, Nick; Turner, Sean (2023-03-29). "Messaging Layer Security: Secure and Usable End-to-End Encryption". IETF . Retrieved 2023-07-28.
  9. "New MLS protocol provides groups better and more efficient security at Internet scale". 2023-07-19. Retrieved 2023-07-28.
  10. Beurdouche, Benjamin; Vasquez, Sarah (2023-07-20). "Messaging Layer Security is now an internet standard". Mozilla . Retrieved 2023-07-28.