Authentication is critical to application security. This writeup explores modern authentication patterns, their trade-offs, and implementation best practices.
OAuth2 and OpenID Connect
OAuth2 provides delegated authorization, while OpenID Connect adds authentication on top. These standards enable secure single sign-on and third-party integrations.
JWT Token-Based Authentication
JSON Web Tokens are self-contained tokens that carry user information. They enable stateless authentication but require careful handling to prevent security vulnerabilities.
// Verify JWT token
const decoded = jwt.verify(token, process.env.JWT_SECRET);
// Generate new token
const token = jwt.sign(
{ userId: user.id, role: user.role },
process.env.JWT_SECRET,
{ expiresIn: '1h' }
);Session Management
Server-side sessions store authentication state on the server. They provide better security control but require sticky sessions or shared session storage in distributed systems.
Security Best Practices
Always use HTTPS, implement CSRF protection, use httpOnly and secure cookies, rotate tokens, implement rate limiting, and never store sensitive data in tokens.
Conclusion
Choose authentication patterns based on your specific requirements. Combine multiple strategies for defense in depth, and always prioritize security over convenience.
Key Takeaways
Use OAuth2/OIDC for third-party authentication
JWTs enable stateless authentication
Always validate and sanitize tokens
Implement proper token expiration and refresh
Security is a continuous process, not a one-time fix