title: What is a difference between PUSH/PULL and DEALER/ROUTER pattern in zmq?
body: <p>I have been learning <strong><code>zmq</code></strong> recently,<br>could someone brief me about<br>the difference between <strong><code>PUSH/PULL</code></strong> and <strong><code>DEALER/ROUTER</code></strong> pattern in <code>zmq</code><br>and<br>when should I use which pattern?</p>