messaging

The Messaging Layer Security (MLS) protocol (RFC 9420) provides a group key agreement protocol for messaging applications. MLS is designed to protect against eavesdropping, tampering, and message forgery, and to provide forward secrecy (FS) and post-compromise security (PCS).

This document describes the architecture for using MLS in a general secure group messaging infrastructure and defines the security goals for MLS. It provides guidance on building a group messaging system and discusses security and privacy trade-offs offered by multiple security mechanisms that are part of the MLS protocol (e.g., frequency of public encryption key rotation). The document also provides guidance for parts of the infrastructure that are not standardized by MLS and are instead left to the application.

While the recommendations of this document are not mandatory to follow in order to interoperate at the protocol level, they affect the overall security guarantees that are achieved by a messaging application. This is especially true in the case of active adversaries that are able to compromise clients, the Delivery Service (DS), or the Authentication Service (AS).

Secure Telephone Identity Revisited (STIR) provides a means of attesting the identity of a telephone caller via a signed token in order to prevent impersonation of a calling party number, which is a key enabler for illegal robocalling. Similar impersonation is sometimes leveraged by bad actors in the text and multimedia messaging space. This document explores the applicability of STIR's Personal Assertion Token (PASSporT) and certificate issuance framework to text and multimedia messaging use cases, including support for both messages carried as a payload in SIP requests and messages sent in sessions negotiated by SIP.

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.

This document defines and registers with IANA a Uniform Resource Name (URN) namespace for usage within messages standardized by the Eurosystem. The URN namespace is managed by Deutsche Bundesbank, which is a member of the European System of Central Banks (ESCB).

This document registers the Enumservice named "vmsg", which is used to facilitate the real-time routing of voice, video, and unified communications to a messaging system. This vmsg Enumservice registers three Enumservice types: "voicemsg", "videomsg", and "unifmsg". Each type also registers the subtypes "sip", "sips", "http", and "https", as well as the subtype "tel" for the "voicemsg" type. [STANDARDS-TRACK]

This document reports the outcome of a workshop held by the Internet Architecture Board (IAB) on the future of Internet messaging. The workshop was held on 6 and 7 October 2004 in Burlingame, CA, USA. The goal of the workshop was to examine the current state of different messaging technologies on the Internet (including, but not limited to, electronic mail, instant messaging, and voice messaging), to look at their commonalities and differences, and to find engineering, research, and architectural topics on which future work could be done. This report summarizes the discussions and conclusions of the workshop and of the IAB. This memo provides information for the Internet community.

This document describes a Uniform Resource Name (URN) namespace that is managed by SWIFT for usage within messages standardized by SWIFT.

This memo specifies a protocol for the encapsulation of the airline specific protocol over IP. This memo provides information for the Internet community. It does not specify an Internet standard of any kind.