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Firewall Configuration
A Firewall is a network security device that monitors and controls incoming and outgoing network traffic based on predetermined security rules.
Packet Filter Simulation
Allowed
0
Blocked
0
Firewall Rules (Top-Down)
1ALLOWTCP : 80
2ALLOWTCP : 443
3DENYTCP : 22
Live Packet Stream
No traffic detected...
Interactive: Add or remove rules to control the flow of traffic. Try adding a rule to ALLOW TCP port 8080 or DENY port 80.
Key Concepts
- Default DenyThe most secure policy is to block EVERYTHING by default, and only explicitly allow what is necessary.
- Stateful InspectionModern firewalls track the state of active connections, allowing return traffic automatically if the outbound request was allowed.
- Order MattersRules are processed top-down. If a packet matches rule #1 (Allow), it is let through immediately, even if rule #2 says (Deny).
Common Ports
Port 80 (HTTP)Unencrypted web traffic. Often allowed for public web servers.
Port 443 (HTTPS)Encrypted web traffic. The standard for secure browsing.
Port 22 (SSH)Secure Shell for remote administration. Should usually be restricted to specific IPs.