Donald Hester
IP Subnetting using CIDR notation
By far this is the part of networking that scares students. However, it is not that scary. You just need to understand binary math. Oops I guess that is the scary part. Well not any more. Here are some tips and trick to make it easy.
A great book on the topic is "IP Subnetting made Easy!: A very simple and very clear guide to understanding IP subnetting that won’t leave you pulling your hair out." by John Kowalski. It is only $2.99 for Amazon kindle format.
Cheatsheet
