LearnViz CompSci
Home / Learn / Computer Networks / DNS

Beginner Topic 13 of 50 Computer Networks

DNS

Distributed system translating names to IP addresses.

How it works

DNS is a hierarchical distributed database; a resolver queries root, TLD and authoritative servers to turn names into IPs, caching answers for their TTL. Record types: A, AAAA, CNAME, MX, TXT.

Where it is used

Every URL you open.

Common pitfall

Cached stale records after changes, and DNS being unencrypted unless DoH/DoT is used.

Where it fits in the course

DNS is topic 13 of 50 in Computer Networks, rated Beginner. It follows Routers. The next topic is DHCP.

Practice and explore

How to study this topic

  1. Read the explanation above and restate the definition in your own words.
  2. Open the interactive lesson and answer its mini quiz.
  3. Read the common pitfall, then write a short example that avoids it.
  4. Check your understanding in the Computer Networks quiz, and revisit the topic if you miss a question.

Frequently asked questions

What is DNS?
Distributed system translating names to IP addresses. It belongs to Computer Networks and is a beginner-level topic.
Where do people use DNS?
Every URL you open.
What is the most common mistake with DNS?
Cached stale records after changes, and DNS being unencrypted unless DoH/DoT is used.
What should I learn before this topic?
Start with Routers, the topic just before it in Computer Networks.
How can I practice it?
Answer the mini quiz in the interactive lesson, then take the Computer Networks quiz.
Is DNS hard to learn?
It is a Beginner topic, so it works as an entry point. If the terms are new, read the explanation twice and try the visualizer before the quiz.
How long does it take to learn DNS?
Most learners can read the explanation and finish the interactive lesson in under an hour. Fluency comes from applying the idea, so plan a few short practice sessions with the quiz.
Which topics are related to DNS?
Routers, DHCP, Switches and Hubs are closely connected. The full list is in the related topics section of this page.
What should I study after DNS?
Continue with DHCP, the next topic in Computer Networks.

Related topics