The Microsoft Windows Background Intelligent Transfer Service (BITS) is a component in Microsoft Windows operating systems that takes unused network bandwidth to perform concurrent file transfers between machines.
BITS performs asynchronous file transfers in the foreground or background. BITS features queue administration to prioritize file transfer requests from applications. If a disruption occurs, BITS automatically reconnects and resumes the file transfer when the network or machine returns to service.
Properties of a BITS job
A typical BITS job consists of six steps: A connection is made to the BITS service, a file transfer job is created, files are added to the transfer job, the file transfer job starts, the status of the transfer job is checked, and when the transfer is complete or canceled the job closes. Administrators can adjust the BITS transfer job behavior to adjust job priority, proxy use and notifications for job events. Administrators can create and manage BITS jobs with Windows Remote Management (WinRM) and Windows Management Instrumentation (WMI) PowerShell cmdlets.
Products that use BITS
Microsoft uses BITS for file transfers in numerous products including Windows/Microsoft Update, Windows Server Update Services (WSUS), Microsoft Security Essentials and various instant messaging offerings. Third-party applications that use BITS for file transfers include Specops Deploy for package installation on client systems and WinBITS for download management.
The history of BITS
- Microsoft introduced version 1.0 of BITS in Windows XP in 2001.
- Version 1.2 arrived in mid-2002 to add the Automatic Updates service to Windows 2000.
- Version 1.5 came in late 2003 with Windows Server 2003 and brought command-line support, more upload features and security improvements.
- Version 2.0, released in mid-2004 as an update for multiple OS deployments, added more download features, bandwidth throttling and support for Server Message Block (SMB).
- Released in mid-2007, BITS 2.5 added support for IPv6 and custom HTTP headers, and better HTTP security.
- BITS 3.0, included with Windows Vista and Windows Server 2008, added peer caching, notifications, temporary file access, HTTP redirect handling, additional Group Policy controls and event logging.
- BITS 4.0, released in mid-2009 with Windows 7 and Windows Server 2008 R2, brought token-based security, standalone file server features, refined bandwidth throttling, and revised peer caching.
- BITS 5.0, included with Windows 10 in mid-2016, added improvements to background copy jobs and support for older background copy jobs, and the ability to use BITS through APIs and PowerShell cmdlets.
- Version 10.1 of BITS, part of Windows 10 version 1703 (also known as the Windows 10 Creators Update), refined download and notification features.