Palo Alto Networks (PANW) Certified Network Security Administrator (PCNSA) Practice Exam

Which statement is true about how Palo Alto Networks firewalls monitor traffic on the network?

1. They use port or protocol to identify applications

2. They use application signature to identify applications

3. They do not monitor traffic

4. They rely solely on network layer inspection

The correct answer is: They use application signature to identify applications

Palo Alto Networks firewalls utilize application signatures to accurately identify applications traversing the network. This methodology allows for deep packet inspection, where the firewall analyzes the payload of network packets rather than relying solely on port numbers or protocols. By employing application signatures, the firewall can recognize applications even if they are using non-standard ports or are encapsulated within other protocols. This capability enhances the network's security posture by enabling policies and controls to be applied based on the specific applications in use, providing greater visibility and control over traffic. In contrast, identifying applications solely by port or protocol would not provide the necessary accuracy since many applications can operate on shared ports or may disguise themselves using common protocols. The statement about not monitoring traffic contradicts the fundamental role of a firewall, which is to actively monitor and filter traffic. Relying only on network layer inspection would significantly limit the firewall's capabilities, as many contemporary threats operate at higher layers in the OSI model. Therefore, the use of application signatures is essential for effective application identification and network security within Palo Alto Networks firewalls.