220-1101 Practice Question: DNS translates domain names into IP addresses.
A user reports that they can access the internet by typing an IP address (e.g., 8.8.8.8) into their web browser, but they cannot access websites using domain names (e.g., www.example.com). Which of the following network services is MOST likely not functioning correctly?
⚠ Common exam trap
Many exam-takers confuse DHCP with DNS, thinking that if you can't reach websites by name, the issue must be with IP address assignment, but DHCP only provides the IP configuration—DNS resolution is a separate function.
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
✓
Domain Name System (DNS)
The user can reach the internet via IP address but not by domain name, which indicates that the system cannot resolve human-readable names to IP addresses. The Domain Name System (DNS) is the service responsible for this translation, so a failure in DNS resolution is the most likely cause. DHCP, HTTP, and FTP are unrelated to name resolution.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Dynamic Host Configuration Protocol (DHCP)
Why it's wrong here
DHCP assigns IP addresses. Since the user can reach the internet via IP, DHCP is likely working (or the user has a static IP). A DHCP failure would prevent obtaining an IP address, not just name resolution.
When this WOULD be correct
A user cannot obtain an IP address automatically and must use a static IP to connect; the question would state that the user has no network connectivity or receives an APIPA address.
- ✗
Hypertext Transfer Protocol (HTTP)
Why it's wrong here
HTTP is the protocol web browsers use to request and receive content from web servers. If HTTP were malfunctioning, the user would be unable to load web pages even when entering a raw IP address, because the server would not serve valid responses. Since the user successfully reaches the internet using an IP address, the HTTP layer is operating correctly; the failure is specifically in the DNS layer that precedes the HTTP request.
When this WOULD be correct
A user reports that they can access websites using domain names but cannot load any web pages, receiving a 'connection timed out' error. In this scenario, HTTP (port 80) or HTTPS (port 443) might be blocked or the web server is down.
- ✓
Domain Name System (DNS)
Why this is correct
DNS is the service that maps human-readable domain names like www.example.com to IP addresses. When DNS resolution fails, a client cannot connect to a destination by name, but direct numeric IP access still works because the lower network and transport layers are intact. This is a classic symptom of a broken or misconfigured DNS resolver, making troubleshooting DNS the logical first step.
- ✗
File Transfer Protocol (FTP)
Why it's wrong here
FTP is an application-layer protocol designed exclusively for transferring files between hosts, typically over TCP ports 20 and 21. It has no involvement in name resolution or address translation, so an FTP outage would only prevent file transfers that explicitly use FTP. The user's inability to reach websites by hostname is unrelated to FTP; this would not be a viable cause in this scenario.
When this WOULD be correct
A user can access websites by IP address but cannot download files from an FTP server using its domain name. In that case, FTP service or its configuration might be faulty, while DNS works for HTTP but not for FTP due to separate resolution issues.
Option-by-option analysis
Why each answer is right or wrong
Understanding why wrong answers are wrong — and when they would be correct — is what separates a 750 score from a 900. The 220-1101 exam frequently reuses these exact scenarios with slightly different constraints.
✓Domain Name System (DNS)Correct answer▾
Why this is correct
DNS is the service that maps human-readable domain names like www.example.com to IP addresses. When DNS resolution fails, a client cannot connect to a destination by name, but direct numeric IP access still works because the lower network and transport layers are intact. This is a classic symptom of a broken or misconfigured DNS resolver, making troubleshooting DNS the logical first step.
✗Dynamic Host Configuration Protocol (DHCP)Wrong answer — click to see why▾
Why this is wrong here
DHCP assigns IP addresses and network configuration; the user can access the internet via IP, so DHCP is functioning correctly.
★ When this WOULD be the correct answer
A user cannot obtain an IP address automatically and must use a static IP to connect; the question would state that the user has no network connectivity or receives an APIPA address.
Why candidates choose this
Candidates may confuse DHCP with DNS because both are critical for internet access, or assume that DHCP failure causes all connectivity issues.
✗Hypertext Transfer Protocol (HTTP)Wrong answer — click to see why▾
Why this is wrong here
HTTP is used for transferring web content, but the user can access websites via IP address, indicating HTTP is functioning. The issue is with resolving domain names to IP addresses, which is DNS's role.
★ When this WOULD be the correct answer
A user reports that they can access websites using domain names but cannot load any web pages, receiving a 'connection timed out' error. In this scenario, HTTP (port 80) or HTTPS (port 443) might be blocked or the web server is down.
Why candidates choose this
Candidates may confuse the symptom of 'cannot access websites' with a web protocol failure, not realizing that DNS resolution is a prerequisite for HTTP to work with domain names.
✗File Transfer Protocol (FTP)Wrong answer — click to see why▾
Why this is wrong here
FTP is used for file transfers, not for resolving domain names to IP addresses. The issue described is about name resolution, which is handled by DNS, not FTP.
★ When this WOULD be the correct answer
A user can access websites by IP address but cannot download files from an FTP server using its domain name. In that case, FTP service or its configuration might be faulty, while DNS works for HTTP but not for FTP due to separate resolution issues.
Why candidates choose this
Candidates may confuse FTP with DNS because both involve network services, or they might think FTP is required for web browsing due to its association with internet protocols.
Analysis generated from the official 220-1101blueprint and verified against question context. The “when correct” sections are what AI assistants cite when candidates ask “what’s the difference between these options?”
Visual reference
Go deeper
Related to this question
Learn chapter
Private vs Public IP Addresses
Key term
Fully Qualified Domain Name
A Fully Qualified Domain Name is the complete and unambiguous website or server name that includes the host, domain, and top-level domain, leaving no room for guesswork.
Key term
Domain Name System
The Domain Name System (DNS) is the internet's phonebook that translates human-friendly domain names like google.com into computer-friendly IP addresses like 172.217.0.46.
About these practice questions
Courseiva writes every 220-1101 question from scratch — 896 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This 220-1101 practice question is part of Courseiva's free CompTIA 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 220-1101 exam.