All of the Services in these four Service Sets only provide the Client with information, with the exception of the TransferSubscriptions Service in the Subscription Service Set. In general, these services will not generate audit entries or audit Event Messages. The TransferSubscriptions Service shall generate an audit Event of type AuditSessionEventType or subtypes of it for both successful and failed Service invocations. See OPC 10000-5 for the detailed assignment of the SourceNode, the SourceName and additional parameters. For the failure case, the Message for Events of this type should include a description of why the service failed.
For Clients that support auditing, accessing the TransferSubscriptions Service in the Subscription Service Set shall generate audit entries for both successful and failed invocations of the Service. Invocations of the other Services in this Service Set do not require audit entries. All audit entries should be setup prior to the actual Service invocation, allowing the invocation to contain the correct audit record id.