Routers and Subnetting

Today, I learned about router tables and subnets. Both were easier concepts to me, especially since I could relate them to my life.

Routing tables are information routers hold to deliver data with the most efficient path possible. Obviously, a router has to know how and where to forward data and so routing tables comprise that information. There is an exception to data forwarding if you are in the same subnetwork as you can just forward data directly to the computer without bothering the router.

Routers learn routes from neighboring routers. They are also responsible for keeping the list up-to-date in case a path becomes blocked or terminates. If there is more than one route available, the router chooses the most efficient path.

Routing is a lot like networking with people. You learn things from people you associate with. You also try to keep up-to-date with these people and sometimes, unfortunately, a relationship is terminated like a route. You also want to be efficient so you choose the best route possible.

Subnets allow you to take a class A,B, or C network (all determined by size) and divide it into smaller networks. Class C is reserved for larger networks due to the availability of hosts per network. Class A is reserved for smaller ones since they have less possibilities for hosts per network. But, for example, subnetting allows you to take a large class C network and divide it into smaller subnetworks separated by routers. This allows less IP addresses to go to waste. In an IP address, you can always tell what the subnetwork is by looking at the third octet. 200.200.1 is within the same Class C network as 200.200.2 but the subnet is different, meaning it is on a different router within the network.

I cannot wait to learn more about Layer 3! It is by far the coolest layer I have read about.