Fundamentals of IP addressing and CIDRs

For devices on your network to communicate with each other, an Internet Protocol address (IP address) is required. Each network device, whether it is a computer, laptop, mobile phone, printer, or network router, will need to be assigned an IP address that is routable in each network.

Furthermore, each device's IP address must be unique – you cannot have more than one device with the same IP address. This is just how telephones work. Each telephone has a unique number assigned to it. To call someone on the phone, you need to first know their telephone number and then, dial that number, which results in your call getting connected. In Figure 6.1, you would have noticed that each of the internal devices in the home network had an IP address.

There are two types of IP address: IPv4 and IPv6. We will discuss the key differences between them.

IP address version 4 – IPv4

IPv4 was the first version of the IP addressing...