RFC 3516 (rfc3516) - Page 1 of 8

IMAP4 Binary Content Extension

Network Working Group                                       L. Nerenberg
Request for Comments: 3516                               Orthanc Systems
Category: Standards Track                                     April 2003


                     IMAP4 Binary Content Extension

Status of this Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.  Distribution of this memo is unlimited.

Copyright Notice

   Copyright (C) The Internet Society (2003).  All Rights Reserved.

Abstract

   This memo defines the Binary extension to the Internet Message Access
   Protocol (IMAP4).  It provides a mechanism for IMAP4 clients and
   servers to exchange message body data without using a MIME content-
   transfer-encoding.

1.   Conventions Used in this Document

   The key words "MUST", "MUST NOT", "SHOULD", "SHOULD NOT", and "MAY"
   in this document are to be interpreted as described in [KEYWORD].

   The abbreviation "CTE" means content-transfer-encoding.

2.   Introduction

   The MIME extensions to Internet messaging allow for the transmission
   of non-textual (binary) message content [MIME-IMB].  Since the
   traditional transports for messaging are not always capable of
   passing binary data transparently, MIME provides encoding schemes
   that allow binary content to be transmitted over transports that are
   not otherwise able to do so.

   The overhead of MIME-encoding this content can be considerable in
   some contexts (e.g., slow radio links, streaming multimedia).
   Reducing the overhead associated with CTE schemes such as base64






Nerenberg                   Standards Track