PaloAlto Firewalls Traffic Flow in L3 Zones

 PaloAlto Firewalls Traffic Flow in L3 Zones – Step-by-Step Breakdown

Zone → App Zone — showing exactly how security policies, App-ID, and Threat Prevention work together.

🧭 The flow explained:
1️⃣ Packet enters firewall (source zone assigned)
2️⃣ Route lookup determines destination zone
3️⃣ Security policy evaluation (zone-based rules)
4️⃣ App-ID identifies the application (Layer 7 inspection)
5️⃣ Threat / IPS inspection scans for malware & exploits
6️⃣ Session creation in the session table
7️⃣ Packet forwarded if all checks pass ✅
🚫 Lateral movement attempt? Blocked.
✔ Clean traffic? Forwarded.

💡 Key takeaway:
Every packet is inspected and must match security policy before it is trusted.