The central server that performs health evaluation for NAP is a computer running NPS that is known as a NAP health policy server. In this capacity, the computer running NPS is acting as a RADIUS server accepting RADIUS Access-Request messages from NAP enforcement points (RADIUS clients) such as health registration authorities (HRAs), 802.11 wireless access points, 802.1X-capable switches, NAP-enabled VPN servers, and NAP-enabled DHCP servers.
When deploying NAP health policy servers, you must consider the following planning and design issues:
Existing RADIUS infrastructure
RADIUS server capacity
NPS logging and reporting mode
System health validators