RFC 4551 · PROPOSED STANDARD · 2006

IMAP Extension for Conditional STORE Operation or Quick Flag Changes Resynchronization

Overview

RFC 4551, “IMAP Extension for Conditional STORE Operation or Quick Flag Changes Resynchronization”, is a Proposed Standard document published in June 2006 by A. Melnikov, S. Hole. It updates RFC 3501. It has been obsoleted by RFC 7162 — refer to the newer document for the authoritative version. The canonical text is published by the RFC Editor.

Abstract

Often, multiple IMAP (RFC 3501) clients need to coordinate changes to a common IMAP mailbox. Examples include different clients working on behalf of the same user, and multiple users accessing shared mailboxes. These clients need a mechanism to synchronize state changes for messages within the mailbox. They must be able to guarantee that only one client can change message state (e.g., message flags) at any time. An example of such an application is use of an IMAP mailbox as a message queue with multiple dequeueing clients.

The Conditional Store facility provides a protected update mechanism for message state information that can detect and resolve conflicts between multiple writing mail clients.

The Conditional Store facility also allows a client to quickly resynchronize mailbox flag changes.

This document defines an extension to IMAP (RFC 3501). [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 4551 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
Obsoleted by
RFC 7162
This RFC updates
RFC 3501
Other RFCs from 2006

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