How do updates from WSUS work, and when should we use them?
WSUS is an underlying Prerequisite Service that needs to be in place before you can set up and configure the SCCM role that is called Software Updates.
As mentioned earlier the Software Updates role will also do all the setup and configuration of the WSUS. That said, there are some further steps you need to take care of within the WSUS Console as well as the Active Directory Group Policy Management Console.
There has been, and still is, confusion around whether or not you need a Group Policy setting and Windows Update settings for the clients, since there are different opinions and experiences on this.
Why should I need a policy when the SCCM client is setting it for me? Wouldn't that be the easiest way to go?
Yes, the easiest, but not the safest way.
Well, as long as you have SCCM client agent installed and the Software Update Point (SUP) role working well, it's all good.
However...