Introduction to IP Subnetting

IP subnetting

IP subnetting is a very important aspect of the design and functionality of computer networks. If it’s not organized in an efficient way, it can lead to increased costs and lower network performance.

In the physical world, there are different street names and house numbers on each street to uniquely identify different buildings. Similarly, different networks are identified by different network addresses, and devices on a given network are differentiated by means of a unique host address. Both network and host identification is part of the IP address. Some bits are reserved for network addresses, while the others are used for the host portion.

Now, let’s take an in-depth look at what an IP address looks like:

1. The Network portion: The size, in bits, dictated by the network mask.

2. The Host portion: The remaining bits out of the total 32 as determined by the network mask.

3. The Network Mask: Indicates the size of a network (the total number of IP addresses that make up the network).

Assigning an IP address

Let’s assign IP addresses to three devices PC1, PC2, and PC3 as shown in the figure below.