Networking and Operating Systems

Cyber Warfare Boot Camp – Week 4: Subnetting

Objective: 

Students will continue preparing for proficiency in cyber security by reviewing networking fundamentals.

Links:

Topics Discussed:

  • Network Basics
  • OSI Model
  • TCP/IP Model
  • Network Addressing
  • Subnetting
  • Subnet Mask
  • Octet
  • Host
  • IP Address Classes

Assignment:

  1. Visit the Linux Journey website and scroll down to the “Networking Nomad” section. Click on the “Subnetting” item.
  2. Subnetting is one of those things that you do with a calculator in the real world, but you’re not going to be allowed to take a calculator with you if you take a test like the Network+, CySA+ or CCNA exams, so you better learn how to do it on your own.
  3. The “Subnetting” section of the Linux Journey website gives you a quick explanation of what subnetting is, and how it works. It also provides a subnet math cheat method that should get you through most of the problems you’ll encounter. However, if you want a more thorough understanding of how it works (and trust me, you do) visit the Subnetting.net link for further details.
  4. The “How to Subnet” page at Subnetting.net provides a thorough overview of what subnetting is and how it works. If you’re too lazy to read the page (and I know most of you are) you can watch the Subnetting Tutorial video series, and get a full explanation of what subnetting is, how it works, and how to figure out subnets without the need for a calculator.
  5. Once you understand the patterns of how “borrowing bits” for the subnet mask works, take a look at Professor Messer’s Seven Second Subnetting video. In it, he explains a very effective method of quickly determining the number of subnets, the addresses of the created subnets, the broadcast address, and the first and last usable address from a given IP address and subnet mask presented in CIDR notation.
  6.  With the materials provided here, you should be able to achieve a strong foundation in subnetting, which will allow you to handle a good portion of the questions on the CCNA and Network+ certification exams, as well as have a strong understanding of how packets figure out how to travel from one host to another, even when they’re on very different networks.

Assigned: January 31st, 2019
Teacher Pacing Due Date: February 1st, 2019