SUBNETTING for CCNA students

Master subnetting when taking CCNA exam
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  • Lectures 18
  • Length 1 hour
  • Skill Level Beginner Level
  • Languages English
  • Includes Lifetime access
    30 day money back guarantee!
    Available on iOS and Android
    Certificate of Completion
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About This Course

Published 11/2015 English

Course Description

Course last updated 2016-04-01

Now more than 1000 students!

No Powerpoints, no animations. With just a pen I will teach You how IP subnetting works. From binary math to subnet sizes and exam-like questions to verify Your achieved knowledge!

Remember! 30 days money-back guarantee with no questions asked. I want you to be satisfied with my course. No Happy - No Pay!

Also, please take advantage of the free previews to see way you will get.

After taking this course, which takes less than one hour, you will never again need a subnet calculator. Subnetting can be done without any online subnetting calculator, all you need is a pen and paper and you will be able to create your own cheat sheet. What is my subnet mask? How many usable addresses in my network? What is the broadcast address? All of these questions will be easy to answer after enrolling this course!

After each lesson there is a quiz that verifies the knowledge you just achieved!

This course is good for anyone that needs to fully understand subnetting, including CCNA students!

2016-01-03 Re-recorded lecture about 24 bits example. Free preview!

2016-04-01 New promo-video

What are the requirements?

  • You need to know basic math, like adding 64 with 32.

What am I going to get from this course?

  • understand the structure of IP addresses in relation to subnet masks
  • calculate usable subnet given size requirements
  • Answer certification-type questions regarding subnetting

Who is the target audience?

  • The targets of this course are people with a need to understand the relationship between an IP address and its associated subnet mask.
  • If you need to under stand subnetting to pass any exam where this is required, this course is for you!

What you get with this course?

Not for you? No problem.
30 day money back guarantee.

Forever yours.
Lifetime access.

Learn on the go.
Desktop, iOS and Android.

Get rewarded.
Certificate of completion.


Section 1: Introduction

I introduce myself, my background and why we need subnetting.

Section 2: How to do the math

I explain how the binary numbering system works and how to convert between decimal and binary numbers.

Conversion between binary and decimal
2 questions

Learn how a subnet mask look like in binary. Understand the rules of a valid mask and differentiate those from invalid masks.


Converting binary masks to decimal is not harder than any other binary numbers.

2 questions

A small quiz to validate what you have just learned about binary subnet masks.

Prefix notation
3 questions

Verify your knowledge of prefix notation by answering a few questions.

Section 3: Learn how to define the network.
The Network
Section 4: Supernet or summarize subnets

Supernetting is the opposite to subnetting. When you supernet you group together multiple subnets in one definition, for example in route summarization.


A short history lesson about classfull netmasks.


Start simple, here we look into how a /24 works and looks like.


We look into a smaller subnet.


What happens when we cut a subnet in halves?

The cheat sheet
Section 5: Example questions

Find out how many usablet addresses there are given a specific subnet or prefix.


A tricky question. Dividing a range in smaller parts gives us multiple networks. How big are they? Where are the borders?


We have specific requirements, lets find the best solution.


How we convert from a specific prefix to its corresponding mask.

Tricky question 1
Section 6: Bonus material
Bonus lecture: About me and my other courses

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Instructor Biography

Jimmy Larsson, Senior Consultant, Instructor and CISSP

I have been working in IT since 1991. My focus the last 15 years has been in Routing&Switching and Security. I have certifications in Cisco (CCNA, CCNP, CCSP) since 2000, also certified Checkpoing CCSA/CCSP and ISC2 CISSP. After 20+ years as an IT consultant I have a broad as well as deep knowledge in TCP/IP, routing, switching and firewalling.

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