AWS Network Firewall is like a security guard for your entire Amazon VPC (Virtual Private Cloud). It watches ALL traffic coming in and going out.

Key Points:

• Protects your ENTIRE VPC (not just one server)
• Works from Layer 3 to Layer 7 (covers network to application level)
• Can inspect traffic in ANY direction (in, out, between subnets)

What Can It Inspect?

• Traffic from VPC to Internet (outbound)
• Traffic from Internet to VPC (inbound)
• Traffic to/from Direct Connect (your office connection)
• Traffic to/from Site-to-Site VPN (secure tunnel)
• Traffic between VPCs (peered connections)

What Can It Do?

1. Filter Traffic (Allow, Block, or Alert)

• Allow: Let traffic pass through
• Drop: Block traffic silently
• Alert: Log suspicious traffic (but let it pass)

2. Create Smart Rules

You can create thousands of rules based on:

• IP addresses: Block specific IPs (can filter 10,000s of IPs)