1.4 Relationship to Other Protocols
The FRS Protocol relies directly on RPC, as specified in [C706] and [MS-RPCE] (for message transport), and Remote Registry Protocol, as specified in [MS-RRP] (for remote performance monitoring). It relies indirectly on the Directory Replication Service (DRS) Remote Protocol to replicate its Active Directory objects, as specified in [MS-DRSR].
FRS is a deprecated protocol for DFSreplica sets on Windows Server 2008 R2 operating system. The Distributed File System: Replication (DFS-R) Protocol (as specified in [MS-FRS2]) is used to replicate DFS/SYSVOL replica sets when the DFS-Replication Protocol is available. A DFS replica set is configured for replication over either this protocol or DFS-R, but not both. Functional levels are an extension of the mixed/native mode concept introduced in Windows 2000 operating system to activate new Active Directory features after all the domain controllers in the domain or forest are running the Windows Server 2003 operating system or Windows Server 2008 operating system. When a computer running Windows Server 2003 or Windows Server 2008 is installed and promoted to a domain controller, new Active Directory features are activated by the Windows Server 2003 operating system or Windows Server 2008 operating system over its Windows 2000 counterparts, or by the Windows Server 2008 operating system over its Windows Server 2003 counterparts. Additional Active Directory features are available when all domain controllers in a domain or forest are running Windows Server 2003, and the administrator activates the corresponding functional level in the domain or forest.
To activate the new domain features, all domain controllers in the domain must be running Windows Server 2003 or Windows Server 2008 and the administrator raises the domain functional level to Windows Server 2003 or Windows Server 2008. The functional levels are separate from the revisions of the operating system in that users can upgrade to a new operating system (for example, Windows Server 2008) but not necessarily turn on the Windows Server 2008 functional level in the domains. The domain controllers for that domain will run the Windows Server 2008 operating system but display only the earlier domain functionality (for example, Windows Server 2003). However, a domain controller in a Windows Server 2008 functional level domain must be running the Windows Server 2008 operating system. Network clients can authenticate or access resources in the domain or forest without being affected by the Windows Server 2003 domain or forest functional levels. These levels only affect the way that domain controllers interact with each other.
For SYSVOL replica sets:
If the domain functional level is at Windows Server 2008 level, the DFS-R Protocol is used to replicate SYSVOL replica sets, as specified in [MS-FRS2] and [MS-ADTS] (section 188.8.131.52). See section 2.3 for further details.
If the domain functional level is Windows Server 2003 or earlier, the FRS Protocol is used to replicate SYSVOL replica sets, as specified in [MS-ADTS] (section 184.108.40.206).
For DFS replica sets, administrators can decide to create either NTFRS Active Directory objects or DFS-R Active Directory objects. A server might have some replica trees replicated using FRS and at the same time have other replica trees replicated using DFS-R. But, a replica tree must not be replicated by both FRS and DFS-R at the same time.