title: How do I prevent connections in ZeroMQ?
body: <p>I have a PUSH/PULL set up, but there is nothing stopping someone who know the IP address and port where the PULL socket is binding and sending garbage to it. What is the correct way to prevent this and only allow client I have authorized to connect to it?</p>
  
  <p>If this isn't possible can I just tell the socket to only accept one (the first) connection and ignore any subsequent ones?</p>