Configure Connectivity Command

The Configure Connectivity command allows you to views and modify various setting that influence how the application connects to its data sources. The connectivity configuration is preserved between subsequent runs of the application.

There is one group of configuration settings for OPC Data Access and XML-DA, and a separate group for OPC Unified Architecture. Each setting is briefly explained in the information box below the property grid. You will find further explanation to some settings elsewhere in this documentation, including the Reference part for the corresponding types.

In some cases (typically, after changing some value under Shared Parameters), you may be prompted to restart the application, so that the configuration changes can take effect.

If the Configure RTD server connectivity box is checked in the Options dialog (see Options Command), any connectivity configuration changes that you make will also be taken over by the RTD server, i.e. by the Excel worksheets that reference dynamic data using the RTD function.

The default settings are tuned for high interoperability.

For OPC UA, if you need settings that are tuned for best OPC compliance, select the OPC UA Configuration member, and then, in the property grid, click on the drop-down arrow next to the Standard Name, and select the OpcCompliance value from the list.

The default settings for OPC Unified Architecture allow (and prefer) non-secure connections. Therefore, a non-secure connection is made if the target OPC server has an endpoint that supports that.

You can change this behavior as follows:

In the list on the left side, select the OPC UA Configuration member.
In the Selector category, expand the Isolated Parameters item, then expand the Session Parameters item, and then expand the Endpoint Selection Policy item.
Choose which security modes will be allowed: Click on the drop-down arrow next to the Allowed Message Security Modes, and select a combination of the modes. For example, for all modes except non-secure connections, make sure that Secure is checked, and SecurityNone is unchecked.
If both secure and non-secure modes are allowed (and available from the server), you may choose whether the secure or non-secure mode will be preferred: Click on the drop-down arrow next to the Message Security Preference, and select Negative to prefer the non-secure mode, None for no particular preference, or Positive to prefer the secure modes.

Note that if you select OpcCompliance for the Standard Name on Endpoint Selection Policy or higher in the hierarchy, the secure modes will be preferred, but non-secure mode will still be allowed.