Web Cache - Security and Privacy
Authentication and Authorization
API Authentication
- API keys for cache management
- OAuth 2.0 for admin access
- mTLS for inter-node communication
- Role-based access control (RBAC)
Cache Access Control
- Public vs private caching
- Cache-Control: private (no shared cache)
- Authorization header handling
- Cookie-based access control
Data Encryption
Encryption in Transit
- TLS 1.3 for all connections
- HTTPS termination at cache
- Certificate management
- Perfect forward secrecy
Encryption at Rest
- Encrypted disk storage
- Key management (KMS)
- Encrypted backups
- Secure key rotation
Cache Security
Cache Poisoning Prevention
- Validate origin responses
- Sanitize cache keys
- Limit cache key length
- Ignore suspicious headers
- Rate limit cache writes
DDoS Protection
- Rate limiting per IP
- Connection limits
- Request size limits
- Slow request protection
- Geographic blocking
Privacy Considerations
Sensitive Data Handling
- Never cache sensitive data
- Respect Cache-Control: private
- Clear cache on logout
- Secure cookie handling
- PII detection and filtering
Compliance
- GDPR compliance (data residency)
- Right to erasure (cache purging)
- Audit logging
- Data retention policies
- Privacy by design
Security Best Practices
Cache Configuration
- Disable caching for sensitive URLs
- Set appropriate TTLs
- Use secure cache keys
- Enable compression
- Monitor for anomalies
Incident Response
- Rapid cache purging
- Incident logging
- Automated alerts
- Rollback procedures
- Post-incident analysis
This security guide ensures the web cache protects data and maintains user privacy.