The answer is to create a custom App-ID signature for the proprietary protocol. This is correct because App-ID identifies applications by analyzing traffic patterns and payload signatures, not just port numbers; since the custom application uses TCP port 8080, which is commonly associated with web-browsing, a custom App-ID signature allows the firewall to distinguish the proprietary protocol by its unique behavioral characteristics or packet payload fingerprints without disabling App-ID entirely. On the Palo Alto Networks Certified Network Security Administrator PCNSA exam, this scenario tests your understanding that App-ID is port-agnostic and that custom application identification signatures are the most efficient method for handling non-standard or proprietary applications. A common trap is assuming you must change the port or disable App-ID, but the correct approach is to extend App-ID’s classification engine. Memory tip: think of App-ID as a detective that needs a new “mugshot” (signature) for an unknown suspect, not a change of address (port).
PCNSA App-ID and Content-ID Practice Question
This PCNSA practice question tests your understanding of app-id and content-id. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
A security administrator notices that traffic from a custom application is being incorrectly identified as web-browsing. The application uses a proprietary protocol on TCP port 8080. What is the most efficient way to ensure correct identification without disabling App-ID?
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Create a custom App-ID signature for the proprietary protocol.
Option B is correct because creating a custom App-ID signature allows the firewall to correctly identify the proprietary protocol by its unique traffic patterns, such as packet payload signatures or behavioral characteristics, without disabling App-ID. This is the most efficient method as it leverages App-ID's existing classification engine to distinguish the custom application from web-browsing, even though it uses TCP port 8080.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
✗
Use Application Override with the custom application and specify port 8080.
Why it's wrong here
Application Override forces all traffic on that port to be treated as the specified app, risking misidentification.
✓
Create a custom App-ID signature for the proprietary protocol.
Why this is correct
Custom App-ID signatures enable accurate identification of non-standard applications.
Related concept
Read the scenario before looking for a memorised answer.
✗
Disable App-ID for that security rule to allow all traffic on port 8080.
Create a custom service object for TCP 8080 and add it to a security policy.
Why it's wrong here
Custom service objects only define ports; App-ID still uses default signatures.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often confuse Application Override (which bypasses App-ID) with a custom App-ID signature (which enhances App-ID), leading them to choose option A because it seems simpler, but it actually disables deep inspection and security controls.
Detailed technical explanation
How to think about this question
App-ID uses multiple mechanisms to identify applications, including protocol decoding, behavioral analysis, and custom signatures. A custom App-ID signature can be defined using the Palo Alto Networks signature syntax, which matches on specific byte sequences, packet lengths, or transaction patterns within the TCP stream on port 8080. In real-world scenarios, this is critical for proprietary applications that use non-standard ports or mimic other protocols, ensuring accurate visibility and policy enforcement without sacrificing security.
KKey Concepts to Remember
Read the scenario before looking for a memorised answer.
Find the constraint that changes the correct option.
Eliminate answers that are true in general but not in this case.
TExam Day Tips
→Watch for words such as best, first, most likely and least administrative effort.
→Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
A small business has 20 workstations on the 192.168.1.0/24 network and one public IP from its ISP. The router uses PAT (NAT overload) so all 20 devices share one public address using different source ports. NAT questions test whether you understand the four address terms and which direction each translation applies.
What to study next
Got this wrong? Here's your next step.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
App-ID and Content-ID — This question tests App-ID and Content-ID — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Create a custom App-ID signature for the proprietary protocol. — Option B is correct because creating a custom App-ID signature allows the firewall to correctly identify the proprietary protocol by its unique traffic patterns, such as packet payload signatures or behavioral characteristics, without disabling App-ID. This is the most efficient method as it leverages App-ID's existing classification engine to distinguish the custom application from web-browsing, even though it uses TCP port 8080.
What should I do if I get this PCNSA question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
What is the key concept behind this question?
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
These questions test the same concept from different angles. Work through them to make sure you can recognise it however the exam phrases it.
Variation 1. A network administrator notices that traffic for a custom business application is being incorrectly identified as 'ssl' by the firewall. What is the most efficient way to ensure this application is accurately identified without impacting other SSL traffic?
medium
A.Disable App-ID for the security policy rule that allows this traffic.
B.Upgrade the App-ID database to the latest version.
✓ C.Create an App-ID override for the application's specific IP addresses and ports.
D.Add the application's TCP port to the service definition in the security policy.
Why C: Option C is correct because an App-ID override allows you to manually assign a specific application signature to traffic matching defined IP addresses and ports, ensuring the custom business application is correctly identified without altering the global App-ID database or affecting other SSL traffic. This is the most efficient method as it directly overrides the incorrect identification at the application level, preserving the integrity of other SSL-based application detection.
Variation 2. A security administrator notices that traffic from a custom application is being incorrectly identified as web-browsing. What is the most likely cause?
easy
A.The application signature database is outdated.
B.App-ID is disabled on the security rule.
✓ C.The custom application uses HTTP but no specific App-ID signature.
D.Content-ID is blocking the application.
Why C: Option C is correct because when a custom application uses HTTP but lacks a specific App-ID signature, Palo Alto Networks firewalls default to classifying the traffic as web-browsing (HTTP). App-ID relies on a combination of protocol decoders and application signatures; without a custom App-ID signature defined for the application, the firewall cannot distinguish it from generic HTTP traffic.
Last reviewed: Jun 25, 2026
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
This PCNSA practice question is part of Courseiva's free Palo Alto Networks certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the PCNSA exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.