RFC 6531 · PROPOSED STANDARD · 2012
MON · 27 JUL 2026
SMTP Extension for Internationalized Email
Overview
RFC 6531, “SMTP Extension for Internationalized Email”, is a Proposed Standard document published in February 2012 by J. Yao, W. Mao. It obsoletes RFC 5336. The canonical text is published by the RFC Editor.
Abstract
This document specifies an SMTP extension for transport and delivery of email messages with internationalized email addresses or header information. [STANDARDS-TRACK]
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 6531 is hosted at rfc-editor.org. Available in TXT,HTML.
Relationships to other RFCs
Other RFCs from 2012
- RFC 6530 Overview and Framework for Internationalized Email
- RFC 6532 Internationalized Email Headers
- RFC 6529 Host/Host Protocol for the ARPA Network
- RFC 6533 Internationalized Delivery Status and Disposition Notifications
- RFC 6528 Defending against Sequence Number Attacks
- RFC 6534 Loss Episode Metrics for IP Performance Metrics
- RFC 6527 Definitions of Managed Objects for Virtual Router Redundancy Protocol Version 3
- RFC 6535 Dual-Stack Hosts Using "Bump-in-the-Host"