Authentication vs. Authorization: Verifying Identity vs. Granting Access

Sun, 02 Aug 2026 05:18:32 +0900

Overview

Authentication (AuthN) confirms who a user or system claims to be, typically through credentials like passwords, biometrics, or tokens. Authorization (AuthZ) determines what an already-authenticated identity is permitted to do or access. The two are sequential and often conflated, but security bugs frequently trace back to confusing one for the other — e.g., checking that a user is logged in without checking they’re allowed to see a specific resource.

Security on IT Comparison

Authentication vs. Authorization: Verifying Identity vs. Granting Access

Overview