CISSP – Information Systems Security Architecture Professional (ISSAP) — Question 24

Which of the following types of firewall functions at the Session layer of OSI model?

Answer options

• A. Circuit-level firewall
• B. Application-level firewall
• C. Packet filtering firewall
• D. Switch-level firewall

Correct answer: A

Explanation

The correct answer is A, Circuit-level firewall, as it operates at the Session layer, managing sessions between hosts. The other options do not function at this layer: B is an Application-level firewall that operates at the Application layer, C is a Packet filtering firewall that works at the Network layer, and D does not represent a standard type of firewall in the OSI model.