Network Access Protection (NAP) is a Microsoft technology for controlling network access of a computer, based on its health. It was first included in Windows Vista and Windows Server 2008 and backported to Windows XP Service Pack 3. With NAP, system administrators of an organization can define policies for system health requirements.[1] Examples of system health requirements are whether the computer has the most recent operating system updates installed, whether the computer has the latest version of the anti-virus software signature, or whether the computer has a host-based firewall installed and enabled. Computers with a NAP client will have their health status evaluated upon establishing a network connection. NAP can restrict or deny network access to the computers that are not in compliance with the defined health requirements.
NAP was deprecated in Windows Server 2012 R2[2] and removed from Windows Server 2016.[3]