CISSP: Certified Information Systems Security Professional

Network Access Control (NAC) systems perform posture assessment on endpoints attempting to connect to a network, checking attributes such as installed security protections (antivirus, host firewall, encryption) and OS/patch versions. Based on this compliance check, NAC can grant full access, restrict access, or quarantine non-compliant devices, making it the best fit for verifying endpoint security state and OS versions—something an IPS, AD authentication, or a standard firewall are not designed to do.