[ADD] IoT: OPC-UA Protocol

content/applications/productivity/iot.rst

@@ -12,3 +12,14 @@ Internet of Things (IoT)
 
    iot/config
    iot/devices
+
+.. note::
+   The Open Platform Communications (OPC) Unified Architecture (UA) protocol is now supported by the
+   :abbr:`IoT (Internet of Things)` box. :abbr:`OPC (Open Platform Communications)` :abbr:`UA
+   (United Architecture)` is an open standard that specifies information exchange for industrial
+   communication on devices, between machines and between systems. This includes communication
+   between information technology and operational technology. :abbr:`OPC (Open Platform
+   Communications)` :abbr:`UA (United Architecture)` can be used with any software platform, on a
+   wide variety of devices, and deployed securely. The :abbr:`IoT (Internet of Things)` box has
+   entered the world of the Industry 4.0 standard and can be utilized in a wide variety of
+   industries, and for things like building automation, packaging, utilities, etc.