1.3.1 Background

The Group Policy: Core Protocol (as specified in [MS-GPOL]) allows clients to discover and retrieve policy settings created by administrators of a domain. These settings are persisted within Group Policy Objects (GPOs) that are assigned to Policy Target accounts in the Active Directory. On each client, each GPO is interpreted and acted upon by software components known as client plug-ins. The client plug-ins responsible for a given GPO are specified using an attribute on the GPO. This attribute specifies a list of globally unique identifier (GUID) lists. The first GUID of each GUID list is referred to as a client-side extension GUID (CSE GUID). Other GUIDs in the GUID list are referred to as tool extension GUIDs. For each GPO that is applicable to a client, the client consults the CSE GUIDs listed in the GPO to determine which client plug-in on the client will handle the GPO. The client then invokes the client plug-in to handle the GPO.

Registry-based settings are accessible from a GPO through the Group Policy: Registry Extension Encoding protocol [MS-GPREG], which is a client plug-in. The protocol provides mechanisms both for administrative tools to obtain metadata about registry-based settings and for clients to obtain applicable registry-based settings.

Group Policy: Registry Extension Encoding settings are specified using registry policy files (as specified in [MS-GPREG] section 2.2.1). An administrative tool uses the information within the administrative template to write out a registry policy file and associate it with a GPO. The Group Policy: Registry Extension Encoding plug-in on each client reads registry policy files specified by applicable GPOs and applies their contents to its registry.