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<body class="manpage">
<div id="header">
<h1>
nn_pair(7) Manual Page
</h1>
<h2>NAME</h2>
<div class="sectionbody">
<p>nn_pair -
   one-to-one scalability protocol
</p>
</div>
</div>
<div id="content">
<div class="sect1">
<h2 id="_synopsis">SYNOPSIS</h2>
<div class="sectionbody">
<div class="paragraph"><p><strong>#include &lt;nanomsg/nn.h&gt;</strong></p></div>
<div class="paragraph"><p><strong>#include &lt;nanomsg/pair.h&gt;</strong></p></div>
</div>
</div>
<div class="sect1">
<h2 id="_description">DESCRIPTION</h2>
<div class="sectionbody">
<div class="paragraph"><p>Pair protocol is the simplest and least scalable scalability protocol. It allows
scaling by breaking the application in exactly two pieces. For example,
if a monolithic application handles both accounting and agenda of HR department,
it can be split into two applications (accounting vs. HR) that are run on two
separate servers. These applications can then communicate via PAIR sockets.</p></div>
<div class="paragraph"><p>The downside of this protocol is that its scaling properties are very limited.
Splitting the application into two pieces allows to scale to two servers.
To add the third server to the cluster, application has to be split once more,
say be separating HR functionality into hiring module and salary computation
module. Whenever possible, try to use one of the more scalable protocols
instead.</p></div>
<div class="sect2">
<h3 id="_socket_types">Socket Types</h3>
<div class="dlist"><dl>
<dt class="hdlist1">
NN_PAIR
</dt>
<dd>
<p>
    Socket for communication with exactly one peer. Each party can send messages
    at any time. If the peer is not available or send buffer is full subsequent
    calls to <a href="nn_send.3.html">nn_send(3)</a> will block until it&#8217;s possible to send the
    message.
</p>
</dd>
</dl></div>
</div>
<div class="sect2">
<h3 id="_socket_options">Socket Options</h3>
<div class="paragraph"><p>No protocol-specific socket options are defined at the moment.</p></div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_see_also">SEE ALSO</h2>
<div class="sectionbody">
<div class="paragraph"><p><a href="nn_bus.7.html">nn_bus(7)</a>
<a href="nn_pubsub.7.html">nn_pubsub(7)</a>
<a href="nn_reqrep.7.html">nn_reqrep(7)</a>
<a href="nn_pipeline.7.html">nn_pipeline(7)</a>
<a href="nn_survey.7.html">nn_survey(7)</a>
<a href="nanomsg.7.html">nanomsg(7)</a></p></div>
</div>
</div>
<div class="sect1">
<h2 id="_authors">AUTHORS</h2>
<div class="sectionbody">
<div class="paragraph"><p>Martin Sustrik &lt;<a href="mailto:sustrik@250bpm.com">sustrik@250bpm.com</a>&gt;</p></div>
</div>
</div>
</div>
<div id="footnotes"><hr /></div>
<div id="footer">
<div id="footer-text">
nanomsg 0.3-beta-2-g8ae44eb-dirty<br />
Last updated 2014-03-04 23:29:50 CET
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