The ResourceUri parameter of DataType String enables the transport implementation to look up a configured key from the corresponding KeyCredentialConfigurationType instance defined in OPC 10000-12 to use for authenticating access to the broker at the connection level or for queues configured below the connection.

If null, no authentication or anonymous authentication shall be assumed as default unless authentication settings are provided on a subordinated WriterGroup or a DataSetWriter to authenticate access to individual queues.