This chapter provided you with an important understanding of subnetting in IPv4, the easy way. If you keep on practicing, you should be able to subnet any number in under 30 seconds. I presented the diagrams, broken down and color-coded, so you can see what each part of the diagram does. If you learn the bit-to-decimal table, and if you memorize it thoroughly, you are good to go. Also, we have an image of three routers configured with the Class A scheme we created, and I configured the routing protocol RIPv2, so you can visualize what we are trying to accomplish.
When answering questions on IPv4 addressing, be careful with the subnet zero pitfall. Remember, use the zero, do not subtract 2 from the network side. Do not use zero, subtract 2 from the network side.
Next up, we will study VLSM and route summarization.