When some of you read the title of this, I could almost swear that I heard someone gasp in fear of the skill that setting up Internet sharing would take with a Linux box. Actually, if you have the basics down and something to use as a reference, it is really not that bad.

The computer world was similar to all of us having an apple each till some time back. And then the wise men from the industry made networks. Ideas started flowing all over and soon came in the internet. The internet has been the best thing that has happened to the computer world so far. It has created a platform where we can share our ideas.

Since the Internet is a large network composed of smaller networks, it made sense to break the address space into smaller chunks. Network classes enable us to break down this address space. In IPv4 the various classes of networks are -

Class A networks have an address range between 1.0.0.1 to 126.255.255.254 and support 16 million hosts on each of 127 networks.
Class B networks have an address range between 128.1.0.1 to 191.255.255.254 and support 65,000 hosts on each of 16,000 networks.
Class C networks have an address range between 192.0.1.1 to 223.255.254.254 and support 254 hosts on each of 2 million networks.
Class D networks have an address range between 224.0.0.0 to 239.255.255.255 and are reserved for multicast groups.
Class E networks have an address range between 240.0.0.0 to 254.255.255.254 and are reserved for the future