TCP/IP Subnetting

As I have mentioned before I have been working with computer networks for the past 10 years or so. One of the most challenging concepts that I have encountered while I studying to get my CCNA was learning how to Subnet and how to subnet the subnets using Variable Length Subnet Masks (VLSM).

I quickly found out that if you do not have a solid foundation on how to subnet and how to use VLSM’s you will have a hard time understanding and implementing other networking features. These features would include IP Access Lists, Route Maps, Policy Maps, Distribution Lists… Basically anything where you would need to define a set of network parameters to do something, such as blocking certain hosts from telneting or SSHing into a router or switch, defining which networks are allowed access the internet and share a PUBLIC IP ADDRESS using NAT/PAT and defining interesting traffic for an ISDN Back-up Link for automatic failover.

The list of network features grows as you climb your certification ladder. This is not limited to Cisco Networking.  You will see this when you are in the Microsoft world, NET + world, and Security + world just to name a few.  This basic concept is your FOUNDATION to which you build on. I have learned the hard way when I struggled through the CCNA Semesters 1-4 courses and CCNP Semesters 1-4 courses in College.

I am a firm believer that if I did better in that section I could have done better than what I did. Moreover, I believe that was the main reason I failed my first attempt at taking the 640-802 CCNA exam back in 2008.

Now there is no one way in learning how to Subnet. I have seen many examples over my career. Some methods were better than others in my opinion. I think the best method that I have seen and from what I have retained was by watching the CBT Nuggets led by the instructor Jeremy Cioara.

I have found the 3 videos from the ICND1 and ICND2 series on the official CBT Nuggets channel on youtube. The list of the videos with links is below:



I found this the easiest way to subnet and VLSM by watching these videos. Not only was it faster than the ways I have seen in official Cisco Press Material, 3^rd party Books or led by Instructors.

The videos are laid out in a logical and cohesive manner explained everything step by step. I keep these videos book marked to review and to refresh my Subnetting skills. Jeremy has stated before that the New Cisco exams are now Real World based and that this is something that you will need to know in order to become the best Network Admin you can be.

If you like the videos you can check out the official CBT Nugget Channel on youtube for Micronuggets and clips of their video series. Or you can support the company buy purchasing the material to help you learn and obtain your certifications. I am a believer of the videos as I have obtained my CCNA by studying the CCNA Material and Watching Jeremy’s Videos.

I hope you find this post helpful . If you like it, hate it or have suggestions feel free to leave a comment.

RTA