Microsoft Slims Down Windows Updates
From here on out, downloads from Microsoft Update and Automatic Updates will seem just a little bit faster. That is because Microsoft has released a non-security "critical" Windows update that places a permanent copy of the Package Installer for Windows on an end user's computer.
As a result, the footprint of downloads is made significantly smaller.
The Package Installer for Windows, version 126.96.36.199, may be obtained through Microsoft Update or the Microsoft Download Center before it is made mandatory in the near future.
The resident installer will not strip redundant code from software updates released before it went into production, but will allow for smaller downloads in the future, Microsoft says.
Another bandwidth saving measure for updating Windows is the Background Intelligent Transfer Services (BITS) designed for Microsoft Update. BITS downloads software updates in the background using available bandwidth without completely saturating an Internet connection.
More information about the Package Installer for Windows update can be found at the Microsoft Support Knowledge Base.