Authentication vs Authorization
Authentication verifies who you are (login with credentials). Authorization determines what you can do (access control). Both are crucial for secure applications.
JWT vs Session-Based Auth
JSON Web Tokens (JWT) are stateless and work great for APIs and microservices. Session-based auth stores state on the server and is simpler for traditional web apps.
Implementing OAuth 2.0
OAuth 2.0 is the industry standard for authorization. It allows users to grant third-party access without sharing passwords. Use it for "Sign in with Google/GitHub" features.
Security Best Practices
- Always hash passwords with bcrypt or Argon2
- Implement rate limiting on login endpoints
- Use HTTPS everywhere
- Store JWTs in httpOnly cookies
- Implement token refresh mechanisms
- Add two-factor authentication (2FA)