Unknown may be hard word, but there are features of Windows Server 2008 R2 that are not advertised too much, such as DirectAcces or BranchCache features are. R2 version of new server will be supporting couple of interesting new features:
- DNS Security Extensions (DNSSEC): DNS servers and DNS clients can verify the authenticity of a DNS record using public key cryptography. This method can prevent the interception of DNS queries. Early deployment guide can be found here.
- The Active Directory Administrative Center is a new task-oriented user interface for the Active Directory Services. You can perform similar tasks as with the Active Directory Users and Computers console (ADUC). It is based on the new PowerShell cmdlets and displays the PowerShell commands that correspond to the tasks performed with the GUI.
- DHCP Failover: Allows you to work with a primary and a secondary DHCP server. If the primary DHCP server fails, the secondary will take over. Windows Server 2008 R2 supports the DHCP Failover Protocol, which is an Internet Engineering Task Force (IETF) draft. But sadly, this feature is dropped out from final release. Clustering and 20/80 rule are the only ways to achieve DHCP failover! Draft document of this technology can be found here.
- Managed Service Accounts: If the password of an account that is used as identity for services is changed by an admin, the managed service account feature will update all services automatically. (Requires R2 functional level). More info can be found here.
Of course, there are much more improvements in R2 version over 2008 version, complete list can be found here.