thinQmaster Virtual testing partner Adaptive practice exams that find your weak spots and drill them. Every answer explained. From $69
Enroll

thinQmaster

Find your exam

Five questions free, before you decide.

Step 1 · choose a vendor

In one of our camps? Your practice exams come with the tuition — they are on your study page already.

Commonly confused · Security Fundamentals & Crypto

Authentication vs Authorization vs Accounting (AAA): What's the Difference?

Authentication proves who you are, authorization decides what you are allowed to do, and accounting records what you actually did. Together they form the AAA framework.

Authentication

Full definition
vs

Authorization

Full definition
vs

Accounting

AuthenticationAuthorizationAccounting
Question answeredWho are you?What can you do?What did you do?
OrderFirstSecond, after identity is provenThroughout and after the session
MechanismsPasswords, MFA, certificates, biometricsPermissions, ACLs, RBAC, group membershipLogs, audit trails, session records
Failure resultLogin deniedAccess to a resource denied (403)Missing evidence, no traceability
SupportsIdentity verificationLeast privilegeNon-repudiation and auditing
Remember it

AuthN = identity, AuthZ = permissions, Accounting = the receipt.

Exam tip

Watch for scenarios where a user logs in successfully but cannot open a file: that is an authorization issue, not authentication. Log review questions point to accounting.

Tested on

More Security Fundamentals & Crypto look-alikes