September 30, 2019

What Does the 4 Sections of an IP Address Mean?

You might have heard of IP addresses many a times and may have wondered what those digits actually refer to. Read on to understand more about these addresses.

An IP address is a label that is designated to devices that are connected to the internet and make use of the Internet Protocol for data transfer. All IP addresses consist of 32 bits. Here is an example of what that means. Let us take 76.240.249.145 as a sample. All the networking software and hardware and the computer see this address as a 32-bit one, which is subdivided into octets. The term ‘octet’ refers to 8-bit sections. For instance, 01101000 is an octet.

The above IP address can be converted into its binary equivalent with binary arithmetic. In binary form, 76 is 01001100, 240 is 11110000, 249 is 11111001, and 145 is 10010001.

We Do Not Think as Computers Do

Binary code is the language which computers can understand. A computer turns everything to numbers, which for it is a combination of both zeroes and ones. Computers calculate everything with the binary system. So your computer sees the above-mentioned IP address as: 01001100. 11110000. 11111001.10010001

What are These Four Sections about?

Like 76.240.249.145, every IP address is split into two sections, which define your network and your host or computer. Those two parts make up the fundamental structure of IPv4 addresses: the host ID and the network ID. Each computer on the same network shares the same network ID, and each one has its own host ID.

The IP address sections do not need to be split equally – two parts making up the former ID and two address sections comprising the latter one is not something that happens at all times. The network ID maybe 1, 2 or 3 of the sections, leaving the fourth one for the other ID. How each part comes together to define your IP address’s host ID and network ID will determine the Class of network it is associated with. When the network ID of an IP address is defined by its first part, the system will be connected to “Class A” network. These are very large networks and could have around 17 million computers or hosts connected to it.

When the said ID is made up of the initial two sections of the IP address, the system will be connected to a “Class B” network. Smaller compared to Class A networks, the Class B ones can have around 65,000 hosts.

When the ID is made up of the first three parts of the address, the system will be connected to “Class C” network. This network can only accommodate around 254 systems, but there can still be over 2 million of such networks.