Starting in Windows 11, we’ve removed these reverse differentials from the package, thus the package size is significantly smaller. Not only less content for Microsoft to host on our content delivery network, but less content for commercial organizations to transmit and store in their distribution points.
This new cumulative update model resulted in an order of magnitude less content to host compared to the express model, with similar download size. Basically, previous reverse deltas applied, followed by latest forward differentials. This process continues with each new cumulative update. Why? To be saved on disk and used next month to easily bring the previous month’s updated files (RTM +1) back to RTM, then forward to RTM + 2 using the latest forward differentials. This first cumulative update also contains reverse differentials. In this new model for version 1809, the cumulative update is comprised of forward and reverse differentials for each file.įor the first cumulative update after RTM is installed, the forward differentials are used to bring a base version of a file (i.e., the RTM version) forward to the target revision. For the full details on reverse and forward differentials, and the model introduced in Windows 10, version 1809, see Windows Updates using forward and reverse differentials. Specifically, we introduced a model where reverse and forward differentials can be combined to create a smaller cumulative update package compared to the previous express technology. In that release, we introduced significant changes in how we package a cumulative update. To explain, let’s go back to Windows 10, version 1809. But what are reverse differentials and why don’t we need these anymore? How? Through more efficient packaging and removal of reverse differentials from the cumulative update package. The cumulative update size in Windows 11 is approximately 40% smaller than the same set of quality and security updates would have been packaged for Windows 10. This includes a ~40% size reduction in the cumulative update package size, which means there is less to download for end users and commercial organizations alike! Let's take a closer look.
Windows 11 has a redesigned cumulative update approach with better fundamentals to help users install the latest security and quality updates faster and more reliably.