GIAC GSNA Exam - Topic 1 Question 73 Discussion

Actual exam question for GIAC's GSNA exam

Question #: 73
Topic #: 1

[All GSNA Questions]

What does a firewall check to prevent certain ports and applications from getting the packets into an Enterprise?

AThe network layer headers and the session layer port numbers

BThe transport layer port numbers and the application layer headers

CThe application layer port numbers and the transport layer headers

DThe presentation layer headers and the session layer port numbers

Show Suggested Answer

Suggested Answer: B

A firewall stops delivery of packets that are not marked safe by the Network Administrator. It checks the transport layer port numbers and the

application layer headers to prevent certain ports and applications from getting the packets into an Enterprise.

Answer C, A, and D are incorrect. These information are not checked by a firewall.

by Frederick at Jul 14, 2025, 06:55 AM

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Callie

5 months ago

Surprised that people think it's anything other than B!

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Peter

6 months ago

I agree, B is the right choice!

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Paris

6 months ago

I thought firewalls checked session layer stuff too, but B seems solid.

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Jenelle

6 months ago

Wait, are we sure about that? I thought it was more about the network layer.

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Serina

6 months ago

It's definitely the transport layer port numbers and application layer headers.

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Tish

6 months ago

I don't recall much about the presentation layer being involved in firewall checks, so I'm leaning towards option B as well.

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Lisbeth

7 months ago

I feel like it could be option B, but I’m a bit confused about the role of session layer port numbers in this context.

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Avery

7 months ago

I remember practicing a question similar to this, and I think the correct answer is related to the transport layer.

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Anissa

7 months ago

I think firewalls mainly focus on the transport layer port numbers, but I'm not entirely sure if they also check application layer headers.

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Casey

7 months ago

The key here is understanding how firewalls operate at the different OSI layers. I'll need to carefully review the options and think about which layers are most relevant for firewall functionality.

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Lang

8 months ago

Okay, I think I've got this. Firewalls check the transport layer port numbers and the application layer headers to determine what traffic to allow or block.

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Vicki

8 months ago

Hmm, I'm a bit unsure about this one. I know firewalls have something to do with ports and applications, but I'm not sure which specific layers they check.

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Kristofer

8 months ago

This looks like a classic networking question. I'll need to focus on the different OSI layers and how firewalls work to filter traffic.

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Dana

9 months ago

I believe the correct answer is A) The network layer headers and the session layer port numbers because those are the layers where the firewall can control the flow of packets.

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Lezlie

9 months ago

I'm not sure, but I think it could also be the transport layer port numbers and the application layer headers.

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Rolande

10 months ago

I agree with Yong, it makes sense that the firewall would focus on those layers to prevent certain ports and applications.

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Yong

10 months ago

I think the firewall checks the network layer headers and the session layer port numbers.

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Dacia

10 months ago

Haha, the presentation layer? Really? That's like bringing a knife to a gun fight. Definitely B is the way to go.

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Tiera

10 months ago

I agree with Alana. Firewalls are all about the transport and application layers, not the network or presentation layers.

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Nenita

9 months ago

Yes, I agree. Firewalls focus on those layers to prevent certain ports and applications from getting packets into an Enterprise.

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Reta

10 months ago

I think the answer is B) The transport layer port numbers and the application layer headers.

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Option B seems to be the right answer here. The firewall checks the transport layer port numbers and the application layer headers to prevent certain ports and applications from getting the packets into the enterprise.

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Bonita

10 months ago

No, I believe it's option B, the transport layer port numbers and the application layer headers.

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Arlette

10 months ago

I think it's option A, the network layer headers and the session layer port numbers.

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