SSL/TLS (Secure Socket Layer / Transport Layer Security)
Cryptographic protocols for secure communication over networks with certificate management
What is SSL/TLS?
SSL (Secure Sockets Layer) and its successor TLS (Transport Layer Security) are cryptographic protocols that provide secure communication over networks. TLS is the modern standard, though the term "SSL" is still commonly used.
Core Functions:
- Encryption: Protects data in transit
- Authentication: Verifies server identity
- Integrity: Detects data tampering
- Non-repudiation: Prevents denial of communication
- Forward Secrecy: Past sessions remain secure
- Compression: Optional data compression
- Session Resumption: Efficient reconnection
- SNI Support: Multiple certificates per IP
How SSL/TLS Works:
Handshake
Client and server negotiate encryption parameters
→
Key Exchange
Establish shared encryption keys securely
→
Certificate Validation
Verify server identity using digital certificates
→
Secure Communication
Encrypted data transmission begins
SSL/TLS vs HTTP Comparison
| Aspect | HTTP | HTTPS (HTTP over TLS) |
|---|---|---|
| Default Port | 80 | 443 |
| Encryption | None | AES-256 |
| Authentication | None | X.509 Certificates |
| Data Integrity | None | SHA-256 HMAC |
| SEO Impact | Negative | Positive |
| Browser Trust | Warning | Trusted |
🔒 TLS Quick Facts
- SSL 3.0: 1996 (Deprecated)
- TLS 1.0: 1999 (Legacy)
- TLS 1.2: 2008 (Current)
- TLS 1.3: 2018 (Modern)
- Usage: 95%+ of web traffic
Common Applications
Web Browsing (HTTPS)
Secure websites and web applications
Email (SMTPS, IMAPS)
Encrypted email transmission
Database Connections
Secure database communications
API Communications
REST APIs and web services