ISC Practice Question: Systems Security Implementation Verification And Validation
You are verifying that a firewall rule correctly blocks traffic from an unauthorized network. Which tool is best suited for testing this connectivity?
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
nmap -p 80 <target_ip>
Nmap is a standard network scanning tool used to verify that specific ports are blocked or filtered.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
nmap -p 80 <target_ip>
Why this is correct
Nmap allows you to probe a target and confirm if the firewall is effectively filtering the port.
- ✗
nslookup <target_ip>
Why it's wrong here
This is for DNS resolution testing, not port connectivity.
- ✗
netstat -an
Why it's wrong here
This shows local machine socket connections, not network firewall status.
- ✗
ipconfig /all
Why it's wrong here
This shows local network configuration, not remote firewall behavior.
Visual reference
About these practice questions
One of 209 original ISC practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. Learn why practice questions differ from exam dumps →
JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed August 2026 · checked against the official (ISC)² exam blueprint
This ISC practice question is part of Courseiva's free (ISC)² 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 ISC exam.