To determine how they should schedule Windows 10 updates, IT professionals must understand a number of basic concepts related to Windows as a service -- Microsoft's update delivery model that consists of three Windows 10 servicing channels.
Microsoft offers Windows 10 updates as either feature updates or quality updates. Feature updates include new and improved functions and abilities for the OS, similar to traditional versioned releases. Microsoft offers feature updates twice a year, in the spring and fall. Quality updates are minor releases that come out at least once a month and address both security and reliability issues.
The Windows 10 servicing channels are management structures that allow organizations to control how frequently devices receive updates. Each one gives IT a different amount of control.
Microsoft's three Windows 10 servicing channels
Windows Insider Channel is associated with the Windows Insider Program. It enables IT professionals to review updates before they are generally available so they can make sure everything -- apps, devices and more -- is compatible with the new update.
Semi-Annual Channel devices receive Windows 10 updates as soon as they're released for general availability or after a specified amount of time -- though Microsoft sets strict limits on how long IT can defer updates. The Semi-Annual Channel also includes a subcategory, referred to as Semi-Annual Channel (Targeted), which makes it possible to apply an update to a subset of devices before applying it to the entire organization.
Long-Term Servicing Channel is specific to specialized systems, such as medical equipment or ATMs. The devices assigned to this channel usually receive updates every two to three years, although IT can defer updates for up to 10 years. Devices in this channel must run the Long-Term Servicing Branch edition of Windows 10 Enterprise.
How deployment rings in the Semi-Annual Channel work
The deployment rings in the Semi-Annual Channel are essentially concentric circles -- a set of rings starting with a central ring with each circle fully encapsulating the previous circles -- that define the timeline for how to schedule updates. The inner circle receives the updates first and the outer circle receives them last. Of all the Windows 10 servicing channels, this option provides IT with the most flexibility to define device groups.
Windows Insider and the Semi-Annual Channel work in conjunction with these device groupings to determine when devices receive updates based on the servicing channel IT assigns them. Deployment rings provide the structure necessary to schedule updates based on an organization's specific requirements.
For example, an IT professional might define a set of deployment rings made up of four concentric circles. The innermost ring includes only a small number of Windows Insider devices that receive both feature and quality updates as soon as they're available to the Windows Insider Program.
The next deployment ring consists of devices that are part of the targeted Semi-Annual Channel. These devices receive feature and quality updates right after Microsoft releases them for general availability.
In the third ring, IT can set the devices to receive feature updates 100 days after general release and quality updates 10 days after general release.
The fourth ring consists of devices running critical workloads that require the safest update path possible because they can't afford to run into any problems. For these devices, IT might defer updates for the maximum time allowed -- one year for feature updates and 30 days for quality updates. The maximum deferment time for Windows 10 versions 1511 through 1607 is 180 days.