1306 CHAPTER 32 Optimizing Windows Server 2008 R2 for Branch Office Communications into the organization's infrastructure. This chapter covers the use of built-in Windows Server 2008 R2 technologies that help improve the operations, management, administra- tion, and support for branch offices in any organization. In particular, this chapter includes the implementation and use of Read-Only Domain Controllers, the use of two- state domain controller (DC) promotion, an introduction to DFS read-only replicated folders, and the ability to configure administrative role separation. Also covered in this chapter is information enabling BitLocker Drive Encryption, BranchCache, and the latest technologies, which improve WAN utilization between branch offices and hub sites. Understanding Read-Only Domain Controllers (RODCs) One of the new features that received close attention in Windows Server 2008 was a new breed of domain controllers referred to as Read-Only Domain Controllers, also known as RODCs. The RODC hosts a copy of the Active Directory (AD) database like any other writable domain controller, but as its name implies, the contents replica of the domain database residing on the domain controller is read-only and write operations are not supported. It is equally important to mention that the RODCs do not participate in Active Directory replication in the same fashion as writable domain controllers. The fundamental difference between RODC replication and the typical multimaster replication model