Use Background Intelligent Transfer Service (BITS) to transfer files asynchronously between a client and a server. There are three types of transfer jobs. A download job downloads files to the client, an upload job uploads a file to the server, and an upload-reply job uploads a file to the server and receives a reply file from the server application. BITS continues to transfer files after an application exits if the user who initiated the transfer remains logged on and a network connection is maintained. BITS will not force a connection. BITS suspends the transfer if a connection is lost or if the user logs off. BITS persists transfer information while the user is logged off, across network disconnects, and during computer restarts. When the user logs on again, BITS resumes the user's transfer job. For more information, see Users and Network Connections.

This SonicWALL signature identifies legitimate Microsoft download activity over HTTP using MS BITS.