Peer Caching in Background Intelligent Transfer Service (BITS) 4.0

Starting with BITS 4.0, the BITS service was extended to allow subnet-level peer caching for downloaded URL data by using Windows BranchCache. BITS clients can retrieve data from other computers in their own subnet that have already downloaded the data, instead of retrieving the data from remote servers. For more information about Windows BranchCache, see the BranchCache Overview.

If an administrator enables Windows BranchCache on client and server computers in an organization through a group policy or local configuration settings, BITS will use Windows BranchCache for data transfers.

Peer Caching in BITS 3.0

Note  Starting with Windows 7, the BITS 3.0 peer caching model is deprecated. If BITS 4.0 is installed, the BITS 3.0 peer caching model is unavailable.

If the administrator enables peer caching and the job permits downloading content from a peer, BITS will try to download the content from one or more peers. Downloading from a peer is much faster than downloading content from the Internet. Peer caching is disabled by default and jobs must explicitly permit downloading content from peers. An administrator can use a group policy to enable peer caching. After enabling peer caching, the administrator can disable either downloading from a peer or serving content to a peer.

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