RFC 9475 · PROPOSED STANDARD · 2023

Messaging Use Cases and Extensions for Secure Telephone Identity Revisited

Overview

RFC 9475, “Messaging Use Cases and Extensions for Secure Telephone Identity Revisited”, is a Proposed Standard document published in December 2023 by J. Peterson, C. Wendt. The canonical text is published by the RFC Editor.

Abstract

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.

Abstract as published in the RFC, via rfc-editor.org.

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.

Read this RFC

The canonical text of RFC 9475 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.

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