Impersonation

Impersonation is a mechanism that enables a DCOM server to access secured objects using the credentials associated with the client rather than those of the server itself. Impersonation is usually not supported by OPC servers except for those that support the OPC Security specification. If your OPC server supports this specification, consult the vendor documentation for the required impersonation settings for both the client and server computers.

DCOM authorization is supported by the following levels of impersonation:

• Anonymous

  The server can impersonate the client, but the identity of the user associated with the OPC client is hidden from the OPC server.

• Identify

  (Recommended) The OPC server can identify the user associated with the OPC client, and can perform actions as that user.

• Impersonate

  The OPC server can perform actions as the user associated with the OPC client, but is not allowed to access other computers as that user.

• Delegate

  The user that runs the OPC server can act as the user associated with the OPC client, including access to other computers as that user.