title: Alternative to OPC-UA
body: <p>Is there any decent alternative to OPC-UA as a solution for accessing process data of a system composed of various PLCs? Something that is platform independent and can "speak" with products of different brands ?</p>
  
  <p>I've heard of <a href="http://mqtt.org/" rel="noreferrer">MQTT</a> but it seems to be much more like a transport protocol, and only that. It does not have all the higher level stuff like the information modeling, etc.</p>
  
  <p>Thanks for your help!</p>