You can read more about the reference architecture model for Industrie 4.0 (RAMI 4.0), published by ZVEI:<p><a href="http:&#x2F;&#x2F;www.zvei.org&#x2F;Downloads&#x2F;Automation&#x2F;5305%20Publikation%20GMA%20Status%20Report%20ZVEI%20Reference%20Architecture%20Model.pdf" rel="nofollow">http:&#x2F;&#x2F;www.zvei.org&#x2F;Downloads&#x2F;Automation&#x2F;5305%20Publikation%...</a><p>Interestingly, they&#x27;ve settled on OPC UA as <i>the</i> standard for the communications layer.<p>The reference architecture (IIRA) for the American-led effort can be downloaded from the Industrial Internet Consortium:<p><a href="http:&#x2F;&#x2F;www.iiconsortium.org&#x2F;IIRA.htm" rel="nofollow">http:&#x2F;&#x2F;www.iiconsortium.org&#x2F;IIRA.htm</a><p>Last year, the OPC Foundation seemed to be &quot;lobbying&quot; for OPC UA to play a similarly key role in IIRA as it now has in RAMI 4.0, but that did not come to pass.<p>I expect that IEEE P2413 will use IIRA as a starting point. Perhaps OPC UA will be &quot;blessed&quot; as one of several options for the communications layer, but we&#x27;ll have to wait and see.<p>See: <a href="https:&#x2F;&#x2F;standards.ieee.org&#x2F;news&#x2F;2015&#x2F;iic_liaison.html" rel="nofollow">https:&#x2F;&#x2F;standards.ieee.org&#x2F;news&#x2F;2015&#x2F;iic_liaison.html</a>