DSA Factory
Free IP addressing and routing lessonsIP addressing and routing · Stage 0 · Addresses and subnets · Step 1

IPv4 addresses

Read an address as network and host parts, and know the private and special ranges. About 12 minutes.

Quick check

Which of these addresses is a private address that won't be routed on the public Internet?

  1. A172.20.5.9
  2. B8.8.8.8
  3. C172.40.5.9
Show the answer

172.20.5.9. 172.16.0.0 to 172.31.255.255 is a private range.

Lock it in

4 questions on this idea

Short questions that apply the idea to new cases: trace it, work out a number, put steps in order. A wrong answer explains itself.

Answer them in your browserFree account, no card. Your progress is saved, and the idea comes back in a quick review later.
Sign up free to solve