Windows 7: BranchCache

BranchCache is a network performance tool available in Windows 7 and Server 2008.

It acts like a proxy that works only when requested by a client user.

The typical user scenario where BranchCache will be useful is where a branch office has a slow link back to the central office.

Any downloads that might occur will be slow because of the bandwidth connection.

BranchCache is designed for such remote office operations.

There are two modes in which BranchCache works, hosted or distributed.

Hosted mode: a 2008 server located on the branch office hosts the cached files.

Distributed Cache mode: a branch server is not necessary; file copies are directly cached onto the PC’s at the branch location.

When BranchCache is enabled, if there is a request for data across the network, a copy of the data or file is downloaded from the intranet website or a file server and it is cached locally within the branch office.

As the need arises if another user in the branch requests the file, the user gets access to the content almost immediately as it is downloaded from the local cache rather than over a limited bandwidth connection back to headquarters.

Configuring BranchCache

BranchCache requires that you use Windows 7 PCs and Windows Server 2008 R2 servers.

You can use either Group Policy settings or the netsh command-line tool to perform the following configuration tasks on BranchCache clients:

• Enable BranchCache
• Select one of two modes: Distributed Cache or Hosted Cache.
• If using Distributed Cache mode specify the size of the client computers’ cache. BranchCache can use up to 5% of the hard disk drive for the cache.
• If using Hosted Cache mode specify the location where the Hosted Cache will reside.

BranchCache has to be installed on Windows Server 2008 R2.

You must install the BranchCache feature using server manager in order to configure a Web server or an application server that uses the Background Intelligent Transfer Service (BITS) protocol.

You must install the BranchCache for Network Files feature, and configure the server using Group Policy in order to configure a file server to operate with BranchCache.

More detailed configuration details/source material can be found here