In part 2, we installed and configured SQL in order to install Configuration Manager.
In part 3, we installed a stand-alone Primary site.
In the next 16 parts, we will describe how to install the numerous Site Systems roles available in Configuration Manager. Role installation order is not important, you can install roles independently of others.
This part will describe how to install Configuration Manager 2012 R2 Software Update Point (SUP).
The SUP integrates with Windows Server Update Services (WSUS) to provide software updates to Configuration Manager clients.
This is not a mandatory Site System but your need to install a SUP if you’re planning to use SCCM as your patch management platform.
SCCM 2012 SP1 (and thus R2) integrates new features to the Software Update Point that are well documented in this Technet Article.
Site System Role Placement in Hierarchy
This Site System is a site-wide option. It’s supported to install this role on a Central Administration Site, child Primary Site, stand-alone Primary Site and Secondary Site.
When your hierarchy contains a Central Administration Site, install a SUP and synchronizes with Windows Server Update Services (WSUS) before you install a SUP at any child Primary Site.
Continue to read the complete blog post here : http://www.systemcenterdudes.com/sccm-2012-software-update-point/