- OPC UA is platform independent ... in fact I wrote my own OPC UA Client for Android
- OPC UA does not need to be secured through VPN due it already has its own encryption and authenticacion using trusted certificates.
And much more:
- The messages can be up to 16 Mbytes in size and also the protocol has the ability to split the message into pieces if some send or receive buffer is smaller. This means that several thousand tags can be read in a single request.
- The documentation is extensive, well structured and available for free to all, but if you are interested then be prepared to read thousands pages.
In short a far superior protocol compared with others in use actually.
It is to be hoped that in the future PLC manufacturers will incorporate it natively into their products.
Siemens and a few other already did.