Which of the following firewall types inspects Ethernet traffic at the MOST levels of the OSI model?
A.
Packet Filter Firewall
B.
Stateful Firewall
C.
Proxy Firewall
D.
Application Firewall
Explanation:
Stateful inspections occur at all levels of the network.
Incorrect Answers:
A: Packet-filtering firewalls operate at the Network layer (Layer 3) and the Transport layer (Layer 4) of the Open
Systems Interconnect (OSI) model.
C: The proxy function can occur at either the application level or the circuit level.
D: Application Firewalls operate at the Application layer (Layer7) of the OSI model.Dulaney, Emmett and Chuck Eastton, CompTIA Security+ Study Guide, 6th Edition, Sybex, Indianapolis, 2014,
pp. 98-100
Stewart, James Michael, CompTIA Security+ Review Guide, Sybex, Indianapolis, 2014, p. 6