OPC DA over a network 2

[sysengineer]

Just out of interest can anybody explain what application layer protocols are used between an OPC client and an OPC DA server? I understand many OPC servers come with a HTTP server for web browser applications however I'm thinking more about Windows based OPC client software such as HMI and SCADA programs.

Also, are standard OPC DA servers built with TCP/IP based networking functionality or is there a specific type of OPC server required for networking?

 

[danw2]

The bane of OPC DA - Windows DCOM.

OPC Foundation has an app note for setting up DCOM, but the OPC Foundation web has all its DA related app notes in favor or the vaporware OPC UA.

These docs have some real world certitude:

OPC and DCOM: 5 things you need to know
Link

Kepware Technologies Remote OPC DA Quick Start Guide (DCOM)
Link

OPC & DCOM Troubleshooting: Quick Start Guide
Link

 

[sysengineer]

Thank you for the response