Windows 11 cummulative security updates are 40 percent smaller due to new packaging approach

Microsoft Shrinks Windows 11 Updates by 40 Percent — Redmondmag.com

How Microsoft reduced Windows 11 update size by 40% – Microsoft Tech Community

Microsoft explained this week that Windows 11 has an improved cumulative update (CU) technology that is said to reduce the CU size by “about 40 percent.”    CUs arrive monthly, and include quality and security patches for Microsoft’s client operating systems. The “cumulative” term means they contain past months’ updates, as well as new updates, so they tend to grow in size month to month. Having smaller CUs arrive promises to save bandwidth, both for Microsoft and its customers. Microsoft has long had a technology that just delivers the changed bits, which are called “differentials,” and that’s now been improved with Windows 11.

The 40 percent CU size reduction claim can be found in this article by Jonathon Ready, a software engineer and program manager at Microsoft. There’s also a longer article by Steve DiAcetis, a member of the Windows fundamentals team. The article by DiAcetis also includes details notable for IT pros using the Windows Standalone Installer tool with Windows 11, as well as language packs.