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Understanding TLS Certificates
Learn about SSL/TLS certificates, how they work, and how to manage them effectively.
Understanding TLS Certificates
TLS certificates are digital documents that authenticate a website's identity and enable encrypted connections. They're issued by Certificate Authorities (CAs) and contain information about the domain, organization, and public key.
How TLS Certificates Work
When a browser connects to a website:
1. The server presents its TLS certificate
2. The browser verifies the certificate with the CA
3. If valid, an encrypted connection is established
4. Data is encrypted using the public key in the certificate
Types of Certificates
Certificate Lifecycle
Certificates have expiration dates (typically 90 days to 1 year). You need to:
Key Points
- •Certificates authenticate website identity
- •Issued by trusted Certificate Authorities
- •Have expiration dates requiring renewal
- •Enable encrypted HTTPS connections
- •Can be free (Let's Encrypt) or paid
Best Practices
- ✓Use automated certificate renewal
- ✓Monitor expiration dates proactively
- ✓Use wildcard certificates for subdomains
- ✓Implement certificate pinning for critical apps
- ✓Keep certificate chains complete
Common Issues
- ✗Expired certificates
- ✗Incomplete certificate chains
- ✗Mismatched domain names
- ✗Self-signed certificates in production
- ✗Missing intermediate certificates