Types of Firewalls

Question 1

Packet Filtering / Stateless

Answer 1

Usually part of a router firewall which permits or denies traffic based on Layer 3 and 4 information. They are stateless because they use a simple policy table look-up that filters traffic based on specific criteria.

Question 2

Stateful Firewalls

Answer 2

These are the most versatile and most common firewalls. They provide stateful packet filtering by using connection information maintained in a state table. Classified at the network layer but also analyzes traffic at Layer 4 and 5.

Question 3

Application gateway firewall

Answer 3

Filters information at Layers 3, 4, 5, and 7. Most of the firewall control and filtering is done in software.

Question 3

Next-Generation Firewalls (NGFW)

Answer 3

Go beyond stateful firewalls by providing:
Integrated intrusion prevention.
Upgrade paths to include future infnormation feeds.
Techniques to address evolving security threats.

Question 4

Host-based

Answer 4

A PC or server with firewall software running on it.

Question 5

Transparent firewall

Answer 5

Filters IP traffic between a pair of bridged interfaces.

Question 5

Hybrid firewall

Answer 5

A combination of the various firewall types.