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?
A.
Application layer
B.
Physical layer
C.
Transport layer
D.
Network layer
Explanation:
Reference:
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