Packet Filter Limits

The packet filter firewall has several limitations not found on more sophisticated firewalls.

First, it has no ability to detect or prevent application level attacks. This ability requires a session aware firewall.

Next, it doesn't hide the protected network from being seen by the outside world. The network is still visible to all other computers and networks on the Internet. More advanced firewalls can hide the protected network from being seen on the Internet. Computers and users on the Internet will only be able to see the firewall and nothing else.

Lastly, the packet filter firewall does not provide advanced services such as auditing and alarm warnings. These useful services are limited to more complex firewalls.