RFC 4959 · PROPOSED STANDARD · 2007

IMAP Extension for Simple Authentication and Security Layer Initial Client Response

Overview

RFC 4959, “IMAP Extension for Simple Authentication and Security Layer Initial Client Response”, is a Proposed Standard document published in September 2007 by R. Siemborski, A. Gulbrandsen. The canonical text is published by the RFC Editor.

Abstract

To date, the Internet Message Access Protocol (IMAP) has used a Simple Authentication and Security Layer (SASL) profile which always required at least one complete round trip for an authentication, as it did not support an initial client response argument. This additional round trip at the beginning of the session is undesirable, especially when round-trip costs are high.

This document defines an extension to IMAP which allows clients and servers to avoid this round trip by allowing an initial client response argument to the IMAP AUTHENTICATE command. [STANDARDS-TRACK]

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 4959 is hosted at rfc-editor.org. Available in TXT,HTML.

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