Cert Week – IPv4 Subnetting and Supernetting

I have just finished teaching a couple of CompTIA  Network+ classes.  One of the subject matter areas that most students struggle with is the concepts around Subnetting, Supernetting, Variable Length Subnet Masking (VSLM), Fixed Length Subnet Masking (FLSM), Classless Interdomain Routing (CIDR),

I recently found this collection of ten videos presented by Practical Networking.  These excellent guides will  tell you everything you need to learn about networking addressing concepts.  Even if your career focus is

These videos can help you to pass a number of certification exams, starting with CompTIA’s IT Fundamentals, A+ Core 1 and Core 2, Network+, and several Cisco certifications, such as the CCNA and CCNP, and even cybersecurity certifications such as CISSP, CASP+, and Security+.

Subnetting Mastery Video Series from Practical Networking

This video series will teach you everything you need to know about Subnetting.

To maximize your retention, it is recommended to watch these videos in order, and take a quick practice break after video 4, video 5, and video 7.In

Video 1, you will learn the basics of subnetting. Every Subnetting problem will ask you to solve for one or more of seven possible attributes. This video explains what each of the attributes are.

In Video 2 of the series, we will show you how to draw the ultimate Subnetting Cheat Sheet. The rest of the videos in this series will show you how to use this Cheat Sheet to answer any subnetting problem in 60 seconds or less.

In Video 3, we will show you how to use the Subnetting Cheat Sheet to solve for all seven attributes of Subnetting (explored in video 1) in 60 seconds or less.

In Video 4 there are four more practice problems to provide further demonstrations of the method and cheat sheet. The first two problems are fairly straight forward. The second two demonstrate a couple specific peculiarities you might encounter in the real world.

In Video 5, we will show you four tricks that will help you solve subnetting problems even faster. With the speed tips in this video, and a little practice, it won’t be unreasonable to be able to solve subnetting questions in as little as 10 seconds.

In Video 6, we show you how to extend the Subnetting Cheat Sheet to allow you to solve problems in the /17-/24 range just as easily as the /25-/32 range.

In Video 7, we show you how to extend the Subnetting Cheat Sheet to allow you to solve problems in the /1-/16 range.
In Part 1 of the FLSM and VLSM Appendix, we explain the Network Doubling logic, and use it to show you how to solve two types of FLSM questions. Then we illustrate 2^N notation, and demonstrate how to use it to answer FLSM questions quickly.

In Part 2 of the FLSM and VLSM Appendix, we unpack Variable Length Subnet Mask questions, and illustrate how to solve them. We then step through a series of examples using VLSM to assign IP addresses to a network.

Supernetting involves taking multiple subnets or IP addresses and aggregating them into a single Network. This video illustrates and discusses the process, and shows you how to solve summarization problems quickly and accurately. The terms Supernetting, IP Aggregation, and IP Summarization are all interchangeable.

Visit PracNet.net for more free resources to learn
Network Engineering and Network Security.

Studying for the CCNA? Check out pracnet.net/ccna for a list of free, high quality training resources covering various CCNA topics

Want to learn the core of networking: How Data flows through a network? Check out the Networking Fundamentals video series


About the Author:

I am a cybersecurity and IT instructor, cybersecurity analyst, pen-tester, trainer, and speaker. I am an owner of the WyzCo Group Inc. In addition to consulting on security products and services, I also conduct security audits, compliance audits, vulnerability assessments and penetration tests. I also teach Cybersecurity Awareness Training classes. I work as an information technology and cybersecurity instructor for several training and certification organizations. I have worked in corporate, military, government, and workforce development training environments I am a frequent speaker at professional conferences such as the Minnesota Bloggers Conference, Secure360 Security Conference in 2016, 2017, 2018, 2019, the (ISC)2 World Congress 2016, and the ISSA International Conference 2017, and many local community organizations, including Chambers of Commerce, SCORE, and several school districts. I have been blogging on cybersecurity since 2006 at http://wyzguyscybersecurity.com

Add a Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.