Packet filtering firewalls are usually a part of a router. In a packet filtering firewall, each packet is compared to a set of criteria before it is forwarded. Depending on the packet and the…

Packet filtering firewalls are usually a part of a router. In a packet filtering firewall, each packet is compared to a set of criteria before it is forwarded. Depending on the packet and the criteria, the firewall can: i)Drop the packet. ii)Forward it or send a message to the originator. At which level of the OSI model do the packet filtering firewalls work?