Subnetting Speed Practice 2

 In 200-301 V1 Ch14: Analyzing IPv4 Subnets, 200-301 V1 Part 4: IPv4 Addressing, CCENT-OLD, IPv4 Address Drills

Just like last Friday’s post, here’s more Subnetting speed practice. But since no one told me how long it’s taking, I’ve added a poll. You can answer the poll based on this week’s questions, last week’s, or any other week.

Suggestions BEFORE CLICKING to see the rest: be ready to start your timer. Be ready to finish all 5 problems.

Your job:  Based on an IP address/mask, identify:

  1. List the number of network, subnet, and host bits
  2. List the number of hosts addresses in the subnet
  3. List the subnet ID, subnet broadcast address, and range of addresses in the subnet

Ready… steady… go!






$40/router to get IPv6?
Subnet Speed Practice #2: Answers
Notify of

Newest Most Voted
Inline Feedbacks
View all comments

[…] May This post makes no sense without reading this post first. The earlier post lists 5 subnetting problems, and tells you to time yourself. The answers are […]


7:05 :\


3:48 !


for all 5 ?! That’s amazing !
I want to see or know your technique


All right! Making progress…


4min 45sec


Is fast typing/writing a part of this? I can do these exercises almost as fast as I can write (with maybe 5-10 seconds to think for each IP address), but I still can’t get under 8 minutes. Do I need to practice writing the solution to one exercise while we mentally solve the next?


It’s about the thinking time. In your example, if you think for 10 seconds, and then N more to write it, I’m ok with counting it as 10 seconds. The exam will not require you to type the answers even – you’ll think the answer, use it to answer a more in depth question, or click a multi guess answer.


I must be dumb as a rock! For this particular set of 5 questions it took me 13min 54sec to do all 5 of them.

Rounding up to 14min and dividing that time by 5 gives me 2.8min each

Are people saying they are doing all 5 questions in 5min or less? If so, I’m doing something very wrong and will never pass this test


Hey Neophyte,
Take a breath! You’ll get there. You just need to practice. I liken it to the idea that if you put together a piece of furniture from Ikea or an office store, it might take a while, and you might not even feel like you did it right. But if you di 30-40 builds as a contractor to the store, you’d be able to do it well, fast, without referencing the instructions. That’s the goal. Seriously, many people have gotten their speed down to a minute or less for each of these kinds of exercises. (If you have my books, check out part 4 of the ICND1 Cert Guide – that’s where it shows the process, and tells you about where to practice.) Hope this helps…


It took me 3 min 2s. But I didn’t write whole addresses, just the changing octets. For example (Ad.1): .0.0 – .1.255; 0.1, 1.254; N8, S15, H9 – 510.
Thank you Wendell for great examples and practise excersises from your book 🙂


exercises* (sorry)


7.47 for all

Contact Us

We're not around right now. But you can send us an email and we'll get back to you, asap.

Would love your thoughts, please comment.x