A network engineer is troubleshooting a Junos policy that allows SMTP traffic from internal mail servers to the internet. The policy matches TCP port 25. Some emails are not being delivered, and the mail server logs show connection timeouts. What is the most likely cause?

The policy does not allow ICMP for SMTP error reporting

The policy does not allow TCP port 110 for POP3

The remote mail server is using TCP port 587 for submission

The policy does not allow UDP port 25 for SMTP

A company is deploying a new application that uses both TCP and UDP on port 9000. The Junos policy must allow this traffic from the internal network to the application server. What is the correct configuration?

Use the junos-any application object

Create a single custom application object with protocol TCP and port 9000

Create a single custom application object with protocol 'any' and port 9000

Create two custom application objects: one for TCP 9000 and one for UDP 9000, and reference both in the policy

Why is UDP commonly used for DNS and voice traffic in security policies?

UDP uses a three-way handshake to establish sessions.

UDP guarantees ordered delivery of packets, ensuring voice quality.

UDP provides connectionless, low-overhead delivery that suits short queries and real-time streams.

UDP provides built-in encryption for secure communication.

Juniper NetworksCertified Specialist, Security (JNCIS-SEC)

Domain 5Objective 2

Ports and Protocols JN0-336 Practice Questions (Page 1)

Part of the Identity-Aware Security Policies domain, which makes up ~12% of our current practice bank. Juniper Networks does not publish an official question count, but from its 90-minute exam (~35–60 total, ~4–7 in this domain), expect 1–2 from this objective — we provide 23 practice questions to prepare you well beyond it. (estimate)

23questions here

5free pages

5concepts

Questions 1–5

1expert · medium
A network engineer is troubleshooting a Junos policy that allows SMTP traffic from internal mail servers to the internet. The policy matches TCP port 25. Some emails are not being delivered, and the mail server logs show connection timeouts. What is the most likely cause?
Select an answer first
2expert · medium
A company is deploying a new application that uses both TCP and UDP on port 9000. The Junos policy must allow this traffic from the internal network to the application server. What is the correct configuration?
Select an answer first
3foundation · easy
Which protocol and port combination is used by IPsec for Internet Key Exchange (IKE) traffic?
Select an answer first
4foundation · easy
Why is UDP commonly used for DNS and voice traffic in security policies?
Select an answer first
5foundation · easy
Which default port and protocol pair is used by SSH for secure remote administration?
Select an answer first

Finished these 5 questions?

Review the revealed explanations, or continue through the curriculum.

Next 5 questions →Back to JN0-336

Free Basic Practice is a study aid with revealable answers — not a scored exam. Examers.io is independent and not affiliated with or endorsed by Juniper Networks. “JN0-336” is a trademark of its owner, used for identification only.

Ports and Protocols JN0-336 Practice Questions (Page 1)

Questions 1–5

A network engineer is troubleshooting a Junos policy that allows SMTP traffic from internal mail servers to the internet. The policy matches TCP port 25. Some emails are not being delivered, and the mail server logs show connection timeouts. What is the most likely cause?

A company is deploying a new application that uses both TCP and UDP on port 9000. The Junos policy must allow this traffic from the internal network to the application server. What is the correct configuration?

Which protocol and port combination is used by IPsec for Internet Key Exchange (IKE) traffic?

Why is UDP commonly used for DNS and voice traffic in security policies?

Which default port and protocol pair is used by SSH for secure remote administration?

Keep studying — Identity-Aware Security Policies