The correct answer is that the packet is permitted by the first ACE. This is because the access control list (ACL) is evaluated sequentially from top to bottom, and the first entry explicitly permits TCP traffic from any source to the destination IP 10.1.1.100 on port 80. Since the attacker’s SYN packet matches both the protocol and the destination parameters exactly, it is allowed immediately, regardless of any subsequent deny statements. On the Cisco CyberOps Associate 200-201 exam, this scenario tests your understanding of ACL processing order and the distinction between packet filtering and stateful inspection—a common trap is assuming an inbound ACL automatically blocks unsolicited SYN packets, but the ACL itself only checks layer 3 and 4 headers; stateful inspection is a separate firewall function. Remember the memory tip: “First match wins, even for SYN.”
200-201 Security Policies and Procedures Practice Question
This 200-201 practice question tests your understanding of security policies and procedures. 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.
Exhibit
access-list 101 permit tcp any host 10.1.1.100 eq 80
access-list 101 permit tcp any host 10.1.1.100 eq 443
access-list 101 deny ip any any
interface GigabitEthernet0/0
ip access-group 101 in
Refer to the exhibit. A network administrator applied this ACL inbound on the external interface of a firewall. An attacker sends a TCP SYN packet with source IP 192.0.2.1 to destination 10.1.1.100 port 80. Which statement accurately describes the packet's treatment?
access-list 101 permit tcp any host 10.1.1.100 eq 80
access-list 101 permit tcp any host 10.1.1.100 eq 443
access-list 101 deny ip any any
interface GigabitEthernet0/0
ip access-group 101 in
A
The packet is permitted because the ACL only denies non-TCP traffic
Why wrong: ACL permits specified TCP ports but denies all other traffic.
B
The packet is denied by the implicit deny at the end
Why wrong: It matches a permit line first, so implicit deny not reached.
C
The packet is denied because there is no permit for source 192.0.2.1
Why wrong: The ACL permits any source.
D
The packet is permitted by the first ACE
The first line matches TCP any to host 10.1.1.100 on port 80.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The packet is permitted by the first ACE
The ACL permits TCP to 10.1.1.100 on port 80, so the SYN packet is permitted. However, since it's inbound, the firewall will still check the state. But the ACL itself allows it. Option A is correct. Option B is incorrect because there is an explicit deny. Option C is incorrect because it is permitted by the first line. Option D is incorrect because it doesn't match deny before.
Key principle: NAT direction and interface roles matter as much as the IP address mapping. Inside/outside designation controls which traffic is translated.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
✗
The packet is permitted because the ACL only denies non-TCP traffic
Why it's wrong here
ACL permits specified TCP ports but denies all other traffic.
✗
The packet is denied by the implicit deny at the end
Why it's wrong here
It matches a permit line first, so implicit deny not reached.
✗
The packet is denied because there is no permit for source 192.0.2.1
The first line matches TCP any to host 10.1.1.100 on port 80.
Related concept
Static NAT maps one inside address to one outside address.
Common exam traps
Common exam trap: NAT rules depend on direction and matching traffic
NAT is not only about the public address. The inside/outside interface roles and the ACL or rule that matches traffic are just as important.
Detailed technical explanation
How to think about this question
NAT questions usually test address translation, overload/PAT behaviour, static mappings and whether the right traffic is being translated. Read the interface direction and address terms carefully.
KKey Concepts to Remember
Static NAT maps one inside address to one outside address.
PAT allows many inside hosts to share one public address using ports.
Inside local and inside global describe the private and translated addresses.
NAT ACLs identify traffic for translation, not always security filtering.
TExam Day Tips
→Identify inside and outside interfaces first.
→Check whether the scenario needs static NAT, dynamic NAT or PAT.
→Do not confuse NAT matching ACLs with normal packet-filtering intent.
Key takeaway
NAT direction and interface roles matter as much as the IP address mapping. Inside/outside designation controls which traffic is translated.
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.
Review the four NAT address types (inside local, inside global, outside local, outside global), PAT port overload, and static vs dynamic NAT use cases. Then practise related 200-201 NAT questions on configuration and troubleshooting.
Security Policies and Procedures — This question tests Security Policies and Procedures — Static NAT maps one inside address to one outside address..
What is the correct answer to this question?
The correct answer is: The packet is permitted by the first ACE — The ACL permits TCP to 10.1.1.100 on port 80, so the SYN packet is permitted. However, since it's inbound, the firewall will still check the state. But the ACL itself allows it. Option A is correct. Option B is incorrect because there is an explicit deny. Option C is incorrect because it is permitted by the first line. Option D is incorrect because it doesn't match deny before.
What should I do if I get this 200-201 question wrong?
Review the four NAT address types (inside local, inside global, outside local, outside global), PAT port overload, and static vs dynamic NAT use cases. Then practise related 200-201 NAT questions on configuration and troubleshooting.
What is the key concept behind this question?
Static NAT maps one inside address to one outside address.
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 →
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 200-201 practice question is part of Courseiva's free Cisco 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 200-201 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.