Diagnosing the current status of a user's desktop or laptop computer when it connects to the network. Network access protection (NAP) ensures that the user's machine is in the "best of health," so that it is not a staging ground for a virus or Trojan. With NAP software required in both the client and server side, it determines if the operating system, Web browser and other applications are up-to-date before allowing access. It also checks the status of the antivirus signatures, the client firewall and other security components. See access control.