Windows Knowledge Base

[Server Tutor] Configure Background Intelligent Transfer Service (BITS)

BITS transfers files using leftover bandwidth. For example, if you are currently using 60 percent of your bandwidth, BITS will only use the remaining 40 percent. BITS also maintains file transfers when a network disconnection occurs, or a computer needs to be restarted: When the network connection is re-established, BITS will continue where it left off.

Note: BITS version 1.0 is included with Windows XP and supports only downloads. BITS version 1.5 is included with Windows Server 2003 and supports both downloads and uploads. Version 1.5 will be available as a redistributable for Windows 2000 and Windows XP following the release of Windows Server 2003. Uploads require Internet Information Services (IIS) server with the BITS server extension installed.

Background Intelligent Transfer Service (BITS) provides smart, bi-directional file transfer
capability for IIS, enabling it to control bandwidth and offer restartable file transfers. BITS
continues a file transfer even after a user closes the application in which the transfer was
started, as long as the user remains logged on. If the user logs off or the network connection
is interrupted, the session is placed on hold and then reinitiated when the user logs on again
or the connection is re-established.

If you want to use BITS to control file transfer, you need to install it via add/remove Programs see Picture-1 below:

Picture-1 Install BITS Services

After the completion of installation, then configure the BITS server extensions for the virtual directories. Open the IIS console, expand the site, right-click the directory, and choose Properties. Then click the BITS Server Extension tab see picture-1 below:

Picture-2  Setup BITS Server Extension

Please refer to Microsoft  Technical Document "Background Intelligent Transfer Service in Windows Server 2003" , you can get the  word format here as well.