<remark><p>Initial published version, copied and modified from XEP-0242 and XEP-0243.</p></remark>
</revision>
</header>
<section1topic='Introduction'anchor='intro'>
<p>The &XSF; defines protocol suites for the purpose of compliance testing and software certification. This document specifies the 2010 compliance levels for XMPP clients and servers. Unless qualified where explicitly noted, support for the listed specifications is REQUIRED for compliance purposes.</p>
<p>* RFC 3920 and RFC 3921 are currently being revised to correct errors, clarify matters that were underspecified, and incorporate feedback based on implementation and deployment experience gained since RFC 3920 and RFC 3921 were published in 2004. Although the compliance level specified herein refers to RFC 3920 and RFC 3921, developers are also advised to consult &rfc3920bis; and &rfc3921bis;, which provide the most up-to-date and accurate description the core XMPP protocols.</p>
<p>** Support can be enabled via an external component or an internal server module/plugin.</p>
<p>*** Support for the Entity Use Cases and Occupant Use Cases is REQUIRED; support for the remaining use cases is RECOMMENDED.</p>
<p>Some of the protocol specifications referenced herein have their own dependencies; developers need to consult the relevant specifications for further information.</p>
<p>Developers are advised to refer to &xep0178; regarding proper implementation of the SASL EXTERNAL mechanism in XMPP.</p>