2.2.21 ORPC Extensions
This section defines the format for well-known ORPC extensions used in the DCOM Remote Protocol. They are well-known as these extensions are defined by the DCOM Remote Protocol itself and can be used by applications or higher-layer protocols without additional specification. These ORPC extensions are sent by applications or higher-layer protocols within the data field of ORPC_EXTENT structures as part of ORPC calls. Each extension has a well-known identifying GUID that is sent within the id field of the ORPC_EXTENT.