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Copyright (C) 2001-2015 Free Software Foundation, Inc.\\
Copyright (C) 2001-2015 Nikos Mavrogiannopoulos
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<title>GnuTLS 3.4.8: Resuming Sessions</title>
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<a name="Resuming-Sessions"></a>
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Previous: <a href="Client-Authentication.html#Client-Authentication" accesskey="p" rel="prev">Client Authentication</a>, Up: <a href="The-TLS-Handshake-Protocol.html#The-TLS-Handshake-Protocol" accesskey="u" rel="up">The TLS Handshake Protocol</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Function-and-Data-Index.html#Function-and-Data-Index" title="Index" rel="index">Index</a>]</p>
</div>
<hr>
<a name="Resuming-sessions"></a>
<h4 class="subsection">3.5.4 Resuming sessions</h4>
<a name="resume"></a><a name="index-resuming-sessions"></a>
<a name="index-session-resumption"></a>
<p>The TLS handshake process performs expensive calculations
and a busy server might easily be put under load. To
reduce the load, session resumption may be used. This
is a feature of the <acronym>TLS</acronym> protocol which allows a
client to connect to a server after a successful handshake, without
the expensive calculations. This is achieved by re-using the previously
established keys, meaning the server needs to store the state of established
connections (unless session tickets are used – <a href="Session-tickets.html#Session-tickets">Session tickets</a>).
</p>
<p>Session resumption is an integral part of <acronym>GnuTLS</acronym>, and
<a href="Session-resumption.html#Session-resumption">Session resumption</a>, <a href="Client-with-Resume-capability-example.html#ex_002dresume_002dclient">ex-resume-client</a> illustrate typical
uses of it.
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