Enabling authentication and trusting OPC Client certificates - OPC Server 4.0

Open Platform Communications (OPC) Server Plugin Guide

OPC Server 4.0

To secure your system, you can enable authentication for connecting to the OPC Server, and select which OPC Client can connect to the OPC Server by trusting their certificates.

Before you begin

The OPC Client must have a valid certificate.

What you should know

When an OPC Client attempts to connect to the OPC Server, the client's certificate is initially rejected.

If you register the OPC Server with an LDS, the LDS certificate is trusted by default.

If you disable authentication, users can connect to the OPC Server without using a trusted certificate.


  1. From the Config Tool home page, open the Plugins task.
  2. Select the OPC Server plugin from the entity browser, and click the OPC Server configuration tab.
  3. In the Authentication section, set the Enabled option to ON.
  4. In the Rejected certificates pane, select a certificate, and click the left arrow to move it to the Trusted certificates pane.

  5. Click Apply.