BranchCache is a cool technology included with Windows Server 2008 R2 and the Enterprise and Ultimate editions of Windows 7 that allows clients in branch offices to create a peer-to-peer cloud of content that is usually stored at the head office location. Rather than having to pull content over a WAN link from a head office, BranchCache allows compatible clients to retrieve data hosted on head office servers from other clients in the branch office that have accessed the same content earlier.

BranchCache is only supported if the WSUS server is running Windows Server 2008 R2. Previous versions of Windows Server do not support BranchCache. BranchCache is also only supported by clients running Windows 7 Enterprise or Ultimate editions. You don't need to have a Windows Server 2008 R2 server in the branch office as you can use WSUS with BranchCache distributed mode.

To configure a Windows Server 2008 R2 WSUS server to support BranchCache, install the BranchCache feature on the server. Once the feature is installed, it will be used in deploying updates. You also need to configure BranchCache on the client computers. This can be accomplished through group policy. BranchCache policies are located in the Computer Configuration\Administrative Templates\Network\BranchCache node. You should configure two of the following three policies:

  • Turn on BranchCache. Enabling this policy enables BranchCache on the client. It is not necessary to install additional components on the client.
  • Set BranchCache Distributed Cache Mode. Configure this policy if there is no Windows Server 2008 R2 server at the branch office which can function as a hosted cache server. The cache is shared between the clients on the branch office network.
  • Set BranchCache Hosted Cache Mode. Configure this policy if there is a Windows SErver 2008 R2 server at the branch office which can function as the hosted cache server. This server will host the BranchCache cache. Hosting the BranchCache cache requires significantly less resources than deploying WSUS in a branch office.

Once these steps have been taken, all future updates retrieved by client computers in the branch office will leverage BranchCache. This will substantially reduce the amount of update traffic pulled across the WAN link. To find out more about using BranchCache with WSUS, consult the following document on TechNet: http://technet.microsoft.com/en-us/library/dd939820(WS.10).aspx