🔐 TLS Encryption & Decryption in AWS Network Firewall

Today, over 90% of internet traffic uses TLS (HTTPS). While this protects confidentiality, it also prevents traditional firewalls from seeing what’s inside the traffic. That’s where TLS inspection in AWS Network Firewall becomes critical. In this article, we’ll cover: Why TLS inspection is required How TLS normally works How AWS Network Firewall performs TLS decryption & inspection Architecture design (EC2 → Firewall → NAT → IGW) Certificate requirements Common deployment mistakes Best practices 🚨 Why TLS Inspection Is Required Without TLS inspection, a firewall can only see: Source IP Destination IP Port (443) Limited SNI/domain info But it cannot see : Malware downloads Command & Control traffic Data exfiltration Exploit payloads Unauthorized SaaS usage Encrypted traffic becomes a blind spot. TLS inspection restores visibility. 🔎 How TLS Normally Works Before encryption begins, two steps happen: 1️⃣ TCP 3-Way Handshake Client → SYN → Server Server → SYN-ACK → Client Client → ACK → Se