- Authentication: Verifies who you are using credentials like usernames, passwords, or biometrics. It's the first step in security.
- Authorization: Determines what you can access based on roles, permissions, or policies. It happens after authentication.
Real-World Analogy (Authentication vs Authorization)
- Authentication: Showing your ID at the entrance to prove who you are.
- Authorization: Being granted access to specific areas of a building based on your role (e.g., employee vs. visitor) Both processes are critical for securing systems and are often used together to ensure robust security.
Comparison and Contrast: Authorization vs. Authentication
| Aspect | Authentication | Authorization |
|---|---|---|
| Definition | Verifies the identity of a user. | Determines what actions or resources a user is allowed to access. |
| Purpose | Ensures the user is who they claim to be. | Grants or denies permission to resources based on policies or roles. |
| Process | Involves validating credentials like passwords, biometrics, or tokens. | Involves checking permissions against roles, policies, or rules. |
| Focus | Answers "Who are you?" | Answers "What can you do?" |
| Data Used | User credentials (username, password, etc.). | User roles, permissions, access control lists (ACLs). |
| When It Happens | The first step in security; occurs before authorization. | Happens after authentication to enforce access controls. |
| Example | Logging in with a username and password. | Allowing access to a specific file, feature, or API endpoint. |
| Technology Examples | OAuth, OpenID Connect, Multi-Factor Authentication (MFA). | Role-Based Access Control (RBAC), Access Control Lists (ACLs). |
Key Differences:
- Order of Operation: Authentication happens before authorization. You must verify identity before deciding permissions.
- Identity vs. Access: Authentication is about proving identity, while authorization is about granting or denying access to resources.
- Use Cases: Authentication handles who gets in, while authorization handles what they can do once inside.
