Desktop Support Technician Interview Practice Test 2026 – Comprehensive Exam Prep

Understanding AAA in networks is the key: authentication verifies who you are, authorization determines what you can do, and accounting logs what you did. Internet Authentication Service provides a centralized AAA service, acting as a RADIUS server (and proxy) that remote access servers, VPNs, and wireless access points can use to verify credentials, apply access policies, and record sessions for auditing. When someone connects, IAS checks the credentials against the directory, enforces who can access which resources, and logs the activity for security and accounting purposes. This centralization simplifies management and strengthens security across many network access points. The other items are handled by different services: DHCP assigns IP addresses, DNS resolves domain names, and file/print servers manage shared resources. So the function of IAS is indeed accounting, auditing, centralized authentication, and authorization.