Firewall, Basic Functions of Firewall, Packet Filtering, How a packet filtering firewall works, Advantages and Disadvantages of Packet filtering - The InfoSec Handbook
Firewall design - SunWorld - January 1996
Packet Filter Firewall and Application Level Gateway - GeeksforGeeks
1 Firewalls A firewall is a system or group of systems that enforces an access control policy between two networks. Cars have this part that separates. - ppt download