blob: 42dd2b87dc620d836f165a6ce3e65bb0265eae18 [file] [log] [blame]
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width,initial-scale=1">
<title>Internet Message Format :: Apache James</title>
<meta name="generator" content="Antora 3.1.2">
<link rel="stylesheet" href="../../../../_/css/site.css">
</head>
<body class="article">
<header class="header">
<nav class="navbar">
<div class="navbar-brand">
<a class="navbar-item" href="https://james.apache.org"><img src="/_/img/james.svg" alt="james logo"> Apache James</a>
<button class="navbar-burger" data-target="topbar-nav">
<span></span>
<span></span>
<span></span>
</button>
</div>
<div id="topbar-nav" class="navbar-menu">
<div class="navbar-end">
<a class="navbar-item" href="#">Home</a>
<div class="navbar-item has-dropdown is-hoverable">
<a class="navbar-link" href="#">Products</a>
<div class="navbar-dropdown">
<div class="navbar-item"><strong>James server</strong></div>
<a class="navbar-item" href="https://github.com/apache/james-project">Repository</a>
<a class="navbar-item" href="https://issues.apache.org/jira/projects/JAMES/issues">Issue Tracker</a>
<hr class="navbar-divider">
<a class="navbar-item" href="https://james.apache.org/mime4j/index.html">Mime4J</a>
<a class="navbar-item" href="https://james.apache.org/jsieve/index.html">jSieve</a>
<a class="navbar-item" href="https://james.apache.org/jspf/index.html">jSPF</a>
<a class="navbar-item" href="https://james.apache.org/jdkim/index.html">jDKIM</a>
<a class="navbar-item" href="https://james.apache.org/hupa/index.html">HUPA</a>
</div>
</div>
<div class="navbar-item has-dropdown is-hoverable">
<a class="navbar-link" href="#">Community</a>
<div class="navbar-dropdown">
<!-- Not ideal but dropping the version in the href requires tweaking james-projet docs module first -->
<a class="navbar-item" href="/james-project/3.6.0/community/mailing-lists.html">Mailing lists</a>
<a class="navbar-item" href="https://gitter.im/apache/james-project"><svg version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 32 32" class="logo-gitter-sign" data-v-44ebcb1a=""><rect x="15" y="5" width="2" height="10"></rect> <rect x="10" y="5" width="2" height="20"></rect> <rect x="5" y="5" width="2" height="20"></rect> <rect width="2" height="15"></rect></svg> Gitter</a>
<a class="navbar-item" href="https://twitter.com/ApacheJames">
<span class="icon">
<svg aria-hidden="true" data-icon="twitter" role="img" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512">
<path fill="#57aaee" d="M459.37 151.716c.325 4.548.325 9.097.325 13.645 0 138.72-105.583 298.558-298.558 298.558-59.452 0-114.68-17.219-161.137-47.106 8.447.974 16.568 1.299 25.34 1.299 49.055 0 94.213-16.568 130.274-44.832-46.132-.975-84.792-31.188-98.112-72.772 6.498.974 12.995 1.624 19.818 1.624 9.421 0 18.843-1.3 27.614-3.573-48.081-9.747-84.143-51.98-84.143-102.985v-1.299c13.969 7.797 30.214 12.67 47.431 13.319-28.264-18.843-46.781-51.005-46.781-87.391 0-19.492 5.197-37.36 14.294-52.954 51.655 63.675 129.3 105.258 216.365 109.807-1.624-7.797-2.599-15.918-2.599-24.04 0-57.828 46.782-104.934 104.934-104.934 30.213 0 57.502 12.67 76.67 33.137 23.715-4.548 46.456-13.32 66.599-25.34-7.798 24.366-24.366 44.833-46.132 57.827 21.117-2.273 41.584-8.122 60.426-16.243-14.292 20.791-32.161 39.308-52.628 54.253z"></path>
</svg>
</span> Twitter
</a>
<a class="navbar-item" href="#"> <svg class="octicon octicon-mark-github v-align-middle" viewBox="0 0 16 16" version="1.1" aria-hidden="true"><path fill-rule="evenodd" d="M8 0C3.58 0 0 3.58 0 8c0 3.54 2.29 6.53 5.47 7.59.4.07.55-.17.55-.38 0-.19-.01-.82-.01-1.49-2.01.37-2.53-.49-2.69-.94-.09-.23-.48-.94-.82-1.13-.28-.15-.68-.52-.01-.53.63-.01 1.08.58 1.23.82.72 1.21 1.87.87 2.33.66.07-.52.28-.87.51-1.07-1.78-.2-3.64-.89-3.64-3.95 0-.87.31-1.59.82-2.15-.08-.2-.36-1.02.08-2.12 0 0 .67-.21 2.2.82.64-.18 1.32-.27 2-.27.68 0 1.36.09 2 .27 1.53-1.04 2.2-.82 2.2-.82.44 1.1.16 1.92.08 2.12.51.56.82 1.27.82 2.15 0 3.07-1.87 3.75-3.65 3.95.29.25.54.73.54 1.48 0 1.07-.01 1.93-.01 2.2 0 .21.15.46.55.38A8.013 8.013 0 0016 8c0-4.42-3.58-8-8-8z"></path></svg> Github</a>
</div>
</div>
<!-- <div class="navbar-item">
<span class="control">
<a class="button is-primary" href="#">Download</a>
</span>
</div> -->
</div>
</div>
</nav>
</header>
<div class="body">
<div class="nav-container" data-component="james-project" data-version="3.6.0">
<aside class="nav">
<div class="panels">
<div class="nav-panel-menu is-active" data-panel="menu">
<nav class="nav-menu">
<button class="nav-menu-toggle" aria-label="Toggle expand/collapse all" style="display: none"></button>
<h3 class="title"><a href="../../index.html">Apache James Server</a></h3>
<ul class="nav-list">
<li class="nav-item" data-depth="0">
<ul class="nav-list">
<li class="nav-item" data-depth="1">
<button class="nav-item-toggle"></button>
<a class="nav-link" href="../index.html">Concepts</a>
<ul class="nav-list">
<li class="nav-item" data-depth="2">
<a class="nav-link" href="../user/index.html">User Model</a>
</li>
<li class="nav-item" data-depth="2">
<button class="nav-item-toggle"></button>
<a class="nav-link" href="../mail/index.html">Emails</a>
<ul class="nav-list">
<li class="nav-item" data-depth="3">
<button class="nav-item-toggle"></button>
<a class="nav-link" href="#mail/messages/index.adoc">mail/messages/index.adoc</a>
<ul class="nav-list">
<li class="nav-item" data-depth="4">
<a class="nav-link" href="#mail/messages/imf.adoc">mail/messages/imf.adoc</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="#mail/messages/mime.adoc">mail/messages/mime.adoc</a>
</li>
</ul>
</li>
</ul>
</li>
<li class="nav-item" data-depth="2">
<button class="nav-item-toggle"></button>
<a class="nav-link" href="../protocols/index.html">Protocols</a>
<ul class="nav-list">
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../protocols/smtp.html">SMTP</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../protocols/pop.html">POP</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../protocols/imap.html">IMAP</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../protocols/jmap.html">JMAP</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../protocols/esmtp.html">ESMTP</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../protocols/lmtp.html">LMTP</a>
</li>
</ul>
</li>
<li class="nav-item" data-depth="2">
<button class="nav-item-toggle"></button>
<a class="nav-link" href="../storage/index.html">Storage</a>
<ul class="nav-list">
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../storage/mailbox.html">Mailboxes</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../storage/users.html">Users</a>
</li>
</ul>
</li>
<li class="nav-item" data-depth="2">
<a class="nav-link" href="../processing/index.html">Processing</a>
</li>
<li class="nav-item" data-depth="2">
<a class="nav-link" href="../configuration.html">Configuration</a>
</li>
<li class="nav-item" data-depth="2">
<a class="nav-link" href="../glossary.html">Glossary</a>
</li>
</ul>
</li>
</ul>
</li>
<li class="nav-item" data-depth="0">
<ul class="nav-list">
<li class="nav-item" data-depth="1">
<button class="nav-item-toggle"></button>
<a class="nav-link" href="../../servers/index.html">Servers</a>
<ul class="nav-list">
<li class="nav-item" data-depth="2">
<button class="nav-item-toggle"></button>
<a class="nav-link" href="../../servers/demo.html">Demo</a>
<ul class="nav-list">
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../../servers/5-minute-demo.html">Short Demo</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../../servers/15-minute-demo.html">Long Demo</a>
</li>
</ul>
</li>
<li class="nav-item" data-depth="2">
<button class="nav-item-toggle"></button>
<a class="nav-link" href="../../servers/basic/index.html">Basic</a>
<ul class="nav-list">
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../../servers/basic/context.html">Context</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../../servers/basic/objectives.html">Objectives</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../../servers/basic/concepts.html">Concepts</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../../servers/basic/architecture.html">Architecture</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../../servers/basic/conf/index.html">Configuration</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../../servers/basic/help.html">Help</a>
</li>
</ul>
</li>
<li class="nav-item" data-depth="2">
<a class="nav-link" href="../../servers/extendable.html">Extendable</a>
</li>
<li class="nav-item" data-depth="2">
<button class="nav-item-toggle"></button>
<a class="nav-link" href="../../servers/distributed.html">Distributed</a>
<ul class="nav-list">
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../../servers/distributed/objectives.html">Objectives and motivation</a>
</li>
<li class="nav-item" data-depth="3">
<button class="nav-item-toggle"></button>
<a class="nav-link" href="../../servers/distributed/architecture/index.html">Architecture</a>
<ul class="nav-list">
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../../servers/distributed/architecture/consistency-model.html">Consistency Model</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../../servers/distributed/architecture/specialized-instances.html">Specialized instances</a>
</li>
</ul>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../../servers/distributed/run.html">Run</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../../servers/distributed/run-docker.html">Run with docker</a>
</li>
<li class="nav-item" data-depth="3">
<button class="nav-item-toggle"></button>
<a class="nav-link" href="../../servers/distributed/configure/index.html">Configuration</a>
<ul class="nav-list">
<li class="nav-item" data-depth="4">
<button class="nav-item-toggle"></button>
<span class="nav-text">Protocols</span>
<ul class="nav-list">
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/imap.html">imapserver.xml</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/jmap.html">jmap.properties</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/jmx.html">jmx.properties</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/smtp.html">smtpserver.xml &amp; lmtpserver.xml</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/smtp-hooks.html">Packaged SMTP hooks</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/pop3.html">pop3server.xml</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/webadmin.html">webadmin.properties</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/ssl.html">SSL &amp; TLS</a>
</li>
</ul>
</li>
<li class="nav-item" data-depth="4">
<button class="nav-item-toggle"></button>
<span class="nav-text">Storage dependencies</span>
<ul class="nav-list">
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/blobstore.html">blobstore.properties</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/cassandra.html">cassandra.properties</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/elasticsearch.html">elasticsearch.properties</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/rabbitmq.html">rabbitmq.properties</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/tika.html">tika.properties</a>
</li>
</ul>
</li>
<li class="nav-item" data-depth="4">
<button class="nav-item-toggle"></button>
<span class="nav-text">Core components</span>
<ul class="nav-list">
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/batchsizes.html">batchsizes.properties</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/dns.html">dnsservice.xml</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/domainlist.html">domainlist.xml</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/healthcheck.html">healthcheck.properties</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/mailetcontainer.html">mailetcontainer.xml</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/mailets.html">Packaged Mailets</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/matchers.html">Packaged Matchers</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/mailrepositorystore.html">mailrepositorystore.xml</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/recipientrewritetable.html">recipientrewritetable.xml</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/usersrepository.html">usersrepository.xml</a>
</li>
</ul>
</li>
<li class="nav-item" data-depth="4">
<button class="nav-item-toggle"></button>
<span class="nav-text">Extensions</span>
<ul class="nav-list">
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/vault.html">deletedMessageVault.properties</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/extensions.html">extensions.properties</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/listeners.html">listeners.xml</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/spam.html">Anti-Spam setup</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/remote-delivery-error-handling.html">About RemoteDelivery error handling</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/collecting-contacts.html">Contact collection</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/collecting-events.html">Event collection</a>
</li>
<li class="nav-item" data-depth="5">
<a class="nav-link" href="../../servers/distributed/configure/dsn.html">ESMTP DSN support</a>
</li>
</ul>
</li>
</ul>
</li>
<li class="nav-item" data-depth="3">
<button class="nav-item-toggle"></button>
<a class="nav-link" href="../../servers/distributed/operate/index.html">Operate</a>
<ul class="nav-list">
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../../servers/distributed/operate/guide.html">Operator guide</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../../servers/distributed/operate/logging.html">Logging</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../../servers/distributed/operate/webadmin.html">WebAdmin REST administration API</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../../servers/distributed/operate/metrics.html">Metrics</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../../servers/distributed/operate/migrating.html">Migrating existing data</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../../servers/distributed/operate/cli.html">Command Line Interface</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../../servers/distributed/operate/cassandra-migration.html">Cassandra migration</a>
</li>
</ul>
</li>
<li class="nav-item" data-depth="3">
<button class="nav-item-toggle"></button>
<a class="nav-link" href="../../servers/distributed/extending/index.html">Extending server behavior</a>
<ul class="nav-list">
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../../servers/distributed/extending/mail-processing.html">Custom mail processing components</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../../servers/distributed/extending/mailbox-listeners.html">Custom Mailbox Listeners</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../../servers/distributed/extending/smtp-hooks.html">Custom SMTP hooks</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../../servers/distributed/extending/webadmin-routes.html">Custom WebAdmin routes</a>
</li>
</ul>
</li>
</ul>
</li>
<li class="nav-item" data-depth="2">
<a class="nav-link" href="../../servers/test.html">Test</a>
</li>
</ul>
</li>
</ul>
</li>
<li class="nav-item" data-depth="0">
<ul class="nav-list">
<li class="nav-item" data-depth="1">
<a class="nav-link" href="../../customization/index.html">Customization</a>
</li>
</ul>
</li>
<li class="nav-item" data-depth="0">
<ul class="nav-list">
<li class="nav-item" data-depth="1">
<a class="nav-link" href="../../development/index.html">Developer Guide</a>
</li>
</ul>
</li>
<li class="nav-item" data-depth="0">
<ul class="nav-list">
<li class="nav-item" data-depth="1">
<button class="nav-item-toggle"></button>
<a class="nav-link" href="../../community/index.html">Community</a>
<ul class="nav-list">
<li class="nav-item" data-depth="2">
<a class="nav-link" href="../../community/mailing-lists.html">Mailing lists</a>
</li>
<li class="nav-item" data-depth="2">
<a class="nav-link" href="../../community/contributing.html">Contributing</a>
</li>
<li class="nav-item" data-depth="2">
<a class="nav-link" href="../../community/guidelines.html">Guidelines</a>
</li>
<li class="nav-item" data-depth="2">
<a class="nav-link" href="../../community/download.html">Download releases</a>
</li>
<li class="nav-item" data-depth="2">
<a class="nav-link" href="../../community/website.html">Building and publishing the website</a>
</li>
<li class="nav-item" data-depth="2">
<a class="nav-link" href="../../community/release.html">Creating an official Apache James release</a>
</li>
<li class="nav-item" data-depth="2">
<a class="nav-link" href="../../community/support.html">Professional support</a>
</li>
<li class="nav-item" data-depth="2">
<button class="nav-item-toggle"></button>
<span class="nav-text">Apache Software Foundation</span>
<ul class="nav-list">
<li class="nav-item" data-depth="3">
<a class="nav-link" href="https://www.apache.org/">ASF</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="https://www.apache.org/foundation/getinvolved.html">Get involved</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="https://www.apache.org/foundation/faq.html">FAQ</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="https://www.apache.org/licenses/">Licenses</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="https://www.apache.org/security/">Security</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="https://www.apache.org/foundation/sponsorship.html">Sponsorship</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="https://www.apache.org/foundation/thanks.html">Thanks</a>
</li>
</ul>
</li>
</ul>
</li>
</ul>
</li>
</ul>
</nav>
</div>
<div class="nav-panel-explore" data-panel="explore">
<div class="context">
<span class="title">Apache James Server</span>
<span class="version">3.6.0 Snapshot</span>
</div>
<ul class="components">
<li class="component">
<div class="title"><a href="../../../../james-distributed-app/3.8.1/index.html">Apache James Distributed Server</a></div>
<ul class="versions">
<li class="version is-latest">
<a href="../../../../james-distributed-app/3.8.1/index.html">3.8.1 SNAPSHOT</a>
</li>
</ul>
</li>
<li class="component is-current">
<div class="title"><a href="../../../3.8.1/index.html">Apache James Server</a></div>
<ul class="versions">
<li class="version is-latest">
<a href="../../../3.8.1/index.html">3.8.1 SNAPSHOT</a>
</li>
<li class="version is-current">
<a href="../../index.html">3.6.0 Snapshot</a>
</li>
</ul>
</li>
<li class="component">
<div class="title"><a href="../../../../james-site/latest/index.html">Apache James Site</a></div>
<ul class="versions">
<li class="version is-latest">
<a href="../../../../james-site/latest/index.html">latest</a>
</li>
</ul>
</li>
</ul>
</div>
</div>
</aside>
</div>
<main class="article">
<div class="toolbar" role="navigation">
<button class="nav-toggle"></button>
<a href="../../../../james-site/latest/homepage.html" class="home-link"></a>
<nav class="breadcrumbs" aria-label="breadcrumbs">
<ul>
<li><a href="../../index.html">Apache James Server</a></li>
<li><a href="imf.html">Internet Message Format</a></li>
</ul>
</nav>
<div class="page-versions">
<button class="version-menu-toggle" title="Show other versions of page">3.6.0 Snapshot</button>
<div class="version-menu">
<a class="version" href="../../../3.8.1/concepts/messages/imf.html">3.8.1 SNAPSHOT</a>
<a class="version is-current" href="imf.html">3.6.0 Snapshot</a>
</div>
</div>
<div class="edit-this-page"><a href="https://github.com/apache/james-project/blob/james-project-3.6.0/docs/modules/concepts/pages/messages/imf.adoc">Edit this Page</a></div>
</div>
<div class="content">
<aside class="toc sidebar" data-title="Contents" data-levels="2">
<div class="toc-menu"></div>
</aside>
<article class="doc">
<h1 class="page">Internet Message Format</h1>
<div class="sect1">
<h2 id="_overview"><a class="anchor" href="#_overview"></a>Overview</h2>
<div class="sectionbody">
<div class="paragraph">
<p>What people casually call "email" actually refers more specifically to a
text message written in a specified format called
<a href="https://en.wikipedia.org/wiki/Email">"Internet Message Format"</a> or "IMF".
After the first IMF specification was published in 1982 there was no looking back.
Email took the world by storm. Today it is arguably the most prevalent means of
communicating with a distant party.</p>
</div>
<div class="paragraph">
<p>IMF is very basic, and is limited to only specifying a syntax for text messages.
For the transmission of images, audio, or other types of data we need to make
use of the <a href="#mail/messages/mime.adoc" class="xref unresolved">MIME</a> specification.
Although IMF forms the base standard upon which
email is based, email today is rarely used without MIME. We therefore consider
for practical purposes that an email message is essentially the equivalent of
a MIME message.</p>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_specifications"><a class="anchor" href="#_specifications"></a>Specifications</h2>
<div class="sectionbody">
<div class="paragraph">
<p>The specifications for Internet Message Format (IMF) form the basis of what we commonly
call "email".</p>
</div>
<div class="sect2">
<h3 id="_rfc822"><a class="anchor" href="#_rfc822"></a>RFC822</h3>
<div class="paragraph">
<p><a href="https://tools.ietf.org/html/rfc822">RFC822</a> ("Standard for the Format of ARPA Internet Text Messages")
was the original standard that defined the format of an email. It was obsoleted by
<a href="#_rfc2822">RFC2822</a>. The definition of an email under this standard was an attempt to take the lessons
learned from the ARPANET and extend the use of text messaging to a broader context.</p>
</div>
<div class="paragraph">
<p>Electronic mail messages are defined as having contents and an envelope. The contents
consist of header fields and, optionally, a body. The body is nothing more than
a (potentially empty) sequence of lines of text.</p>
</div>
<div class="paragraph">
<p>Although this sounds like a an extremely simple concept, to get two completely separate systems
to agree and understand each other is a surprisingly complex problem that most people
today take for granted. Most of RFC822 deals with the nitty-gritty of formatting and parsing
this type of text message.</p>
</div>
<div class="paragraph">
<p>This specification deals with the headers, additionally relating them to the sending and
forwarding of messages. The body content is dealt with in <a href="#RFC2045">[RFC2045]</a></p>
</div>
</div>
<div class="sect2">
<h3 id="_rfc2822"><a class="anchor" href="#_rfc2822"></a>RFC2822</h3>
<div class="paragraph">
<p><a href="https://tools.ietf.org/html/rfc2822">RFC2822</a> ("Internet Message Format")
obsoletes <a href="#_rfc822">RFC822</a>, and was obsoleted by <a href="#_rfc5322">RFC5322</a>.</p>
</div>
<div class="paragraph">
<p>The standard builds on RFC822, but limits its scope to only the sytax of the
message, and obsoletes much of what was defined by RFC822. The envelope was
split into a separate specification, <a href="#RFC2821">[RFC2821]</a>.</p>
</div>
</div>
<div class="sect2">
<h3 id="_rfc5322"><a class="anchor" href="#_rfc5322"></a>RFC5322</h3>
<div class="paragraph">
<p><a href="https://tools.ietf.org/html/rfc5322">RFC5322</a> ("Internet Message Format")
was published in 2008.
It obsoletes <a href="#_rfc2822">RFC2822</a> and is currently the specification still actually in use.</p>
</div>
<div class="paragraph">
<p>It builds on RFC2822, updating it to the then-current context and obsoleting
outdated parts of RFC2822.</p>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_james_model"><a class="anchor" href="#_james_model"></a>James Model</h2>
<div class="sectionbody">
<div class="paragraph">
<p>While the general description of IMF is not sufficient for building a complex
system like James, the technical specifications are unfortunately
very messy and overly-complex due to their history and the context in which
they were developed.</p>
</div>
<div class="paragraph">
<p>Since modern-day messaging almost always requires MIME, and since the
separation between IMF and MIME is not really useful from a usage perspective,
James considers an "email" to be both IMF- an MIME-compliant. For all intents
and purposes, James does not consider the concept of IMF in its domain model.</p>
</div>
</div>
</div>
</article>
</div>
</main>
</div>
<footer class="footer">
<p>This page was built using the Antora default UI.</p>
<p>The source code for this UI is licensed under the terms of the MPL-2.0 license.</p>
</footer>
<script id="site-script" src="../../../../_/js/site.js" data-ui-root-path="../../../../_"></script>
<script async src="../../../../_/js/vendor/highlight.js"></script>
</body>
</html>