The Messaging Layer Security Protocol
RFC 9420, “The Messaging Layer Security Protocol”, is a Proposed Standard document published in July 2023 by R. Barnes, B. Beurdouche, R. Robert, J. Millican, E. Omara, K. Cohn-Gordon. The canonical text is published by the RFC Editor.
Abstract
Messaging applications are increasingly making use of end-to-end security mechanisms to ensure that messages are only accessible to the communicating endpoints, and not to any servers involved in delivering messages. Establishing keys to provide such protections is challenging for group chat settings, in which more than two clients need to agree on a key but may not be online at the same time. In this document, we specify a key establishment protocol that provides efficient asynchronous group key establishment with forward secrecy (FS) and post-compromise security (PCS) for groups in size ranging from two to thousands.
What “Proposed Standard” means
An entry-level standards-track specification: stable, peer-reviewed and a solid basis for implementation, though it may still evolve before becoming an Internet Standard.
The canonical text of RFC 9420 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.
- RFC 9419 Considerations on Application - Network Collaboration Using Path Signals
- RFC 9418 A YANG Data Model for Service Assurance
- RFC 9417 Service Assurance for Intent-Based Networking Architecture
- RFC 9416 Security Considerations for Transient Numeric Identifiers Employed in Network Protocols
- RFC 9424 Indicators of Compromise and Their Role in Attack Defence
- RFC 9415 On the Generation of Transient Numeric Identifiers
- RFC 9425 JSON Meta Application Protocol for Quotas
- RFC 9414 Unfortunate History of Transient Numeric Identifiers