2.6.1 System Versioning and Capability Negotiation
Group Policy protocols each have their own system versioning and capability negotiation.
Group Policy relies on the Group Policy: Core Protocol, as implemented in the core Group Policy engine, for the transport of policy information. It provides a versioning capability in an attribute of the Active Directory object class for a GPO, as described in [MS-GPOL] section 2.2.4. The version number is a simple integer that is also written to the gpt.ini file on the Group Policy file share, as described in [MS-GPOL] section 2.2.4. There is currently only one version, and if the Group Policy client receives anything other than the current version for a GPO, the GPO does not participate in the Group Policy: Core Protocol, as described in [MS-GPOL] section 3.2.5.1.5.
The System Versioning and Capability Negotiation implementation of extension protocols is documented in the respective extension protocol specifications. They are described in the Versioning and Capability Negotiation section of the respective protocol technical documents.