Understanding JWT Authentication

JSON Web Tokens (JWT) have become the standard for implementing authentication in modern web applications. At Nike, we implemented a robust JWT-based authentication system that could handle millions of users securely.

Key Components

Our JWT implementation consisted of several key components:

• Token Generation and Validation
• Secure Storage and Transmission
• Refresh Token Mechanism
• Rate Limiting and Security Measures

Implementation Details

Token Structure

We structured our JWTs with the following claims:

• sub: Subject (user ID)
• iat: Issued at time
• exp: Expiration time
• aud: Audience (application identifier)
• Custom claims for role-based access

Security Measures

To ensure maximum security, we implemented:

• Short-lived access tokens (15 minutes)
• Secure HTTP-only cookies for refresh tokens
• CSRF protection
• Rate limiting on authentication endpoints
• Token blacklisting for revoked tokens

Best Practices

Here are some key best practices we followed:

1. Always validate token signatures
2. Use strong encryption algorithms (RS256)
3. Implement proper token revocation
4. Monitor for suspicious activities
5. Regular security audits

Lessons Learned

The implementation taught us valuable lessons about:

• Importance of proper token management
• Need for comprehensive security measures
• Value of monitoring and logging
• Benefits of standardized authentication