Linux HOWTO: NetMasks Explained
| Linux ipnatctl HOWTO: Selecting What Packets To Mangle | If youre not familiar with the /-notation used for network addresses, it works like this.
Every machine needs an individual address. To keep things simple, we assign them in clumps; each network of machines generally gets a range of addresses.
A single IP address is 32 bits long: printed in binary has 32 binary
digits, each 1 or 0. Its standard to print them as 4 decimal numbers,
each representing 8 bits, such as 192.168.1.1. In binary, this would be 11000000101010000000000100000001.