Which type of firewall is commonly part of a router firewall and allows or blocks traffic based on Layer 3 and Layer 4 information?

Which type of firewall is commonly part of a router firewall and allows or blocks traffic based on Layer 3 and Layer 4 information?

• stateless firewall
• stateful firewall
• proxy firewall
• application gateway firewall
  

  Answers Explanation & Hints: A stateless firewall uses a simple policy table look-up that filters traffic based on specific criteria. These firewalls are usually part of a router firewall. They permit or deny traffic based on Layer 3 and Layer 4 information.