RFC 9051 · PROPOSED STANDARD · 2021

Internet Message Access Protocol - Version 4rev2

Overview

RFC 9051, “Internet Message Access Protocol - Version 4rev2”, is a Proposed Standard document published in August 2021 by A. Melnikov, B. Leiba. It obsoletes RFC 3501. The canonical text is published by the RFC Editor.

Abstract

The Internet Message Access Protocol Version 4rev2 (IMAP4rev2) allows a client to access and manipulate electronic mail messages on a server. IMAP4rev2 permits manipulation of mailboxes (remote message folders) in a way that is functionally equivalent to local folders. IMAP4rev2 also provides the capability for an offline client to resynchronize with the server.

IMAP4rev2 includes operations for creating, deleting, and renaming mailboxes; checking for new messages; removing messages permanently; setting and clearing flags; parsing per RFCs 5322, 2045, and 2231; searching; and selective fetching of message attributes, texts, and portions thereof. Messages in IMAP4rev2 are accessed by the use of numbers. These numbers are either message sequence numbers or unique identifiers.

IMAP4rev2 does not specify a means of posting mail; this function is handled by a mail submission protocol such as the one specified in RFC 6409.

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 9051 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.

Relationships to other RFCs
This RFC obsoletes
RFC 3501
Other RFCs from 2021

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