What is a Firewall?
A network security system that monitors and controls incoming and outgoing traffic.
Detailed Explanation
Firewalls act as barriers between trusted internal networks and untrusted external networks. They use predefined rules to allow or block traffic based on IP addresses, ports, protocols, and application-level data. Modern firewalls can be hardware devices, software applications, or cloud services, and often include features like intrusion detection, VPN support, and deep packet inspection.
Examples
- •Blocking all incoming traffic except port 80 (HTTP) and 443 (HTTPS)
- •Allowing outbound traffic but restricting incoming connections
- •Application firewalls filtering based on HTTP headers