TCP/IP convention with non-routable addresses,subnet masks

After seeing some users do funny stuff with address schemes on other forums, I decided to post this. First of all the deal with the 192.168.x.x address range that’s become so popular is that it’s the non-routable class C IP addess range. Non-routable meaning that Internet routers are programmed to ignore those ranges and Class C referring to a block of 255 Addresses.

So here are the non-routable address ranges
Class A:10.../8 - 16 Million addresses
Class B: 172.16-31.
/16 - 65,536 addresses
Class C:192.168../24 - 255 addresses

The /8, /16, /24 refers to the number of bits in the subnet mask. They’re grouped in 8 bit sets called octets. So /16 =

Read about subnet masks here. They’re basically just a way to separate how many addresses versus how many separate networks you have. If you ever want to get clever with them, just do it like the professionals. Throw away your binary math and type “subnet calculator” into Google. You’ll get a bazillion free subnet calculators.

Here is info about “non-routable” IP ranges in RFC 1918 and good info about
Network Address Translation (NAT). Keep in mind that NAT wasn’t around when RFC 1918 was specified.