Introduction To Subnetting
Subnetting is the process of dividing a larger network into smaller ones in order to maintain security. So, smaller networks require less maintenance. It is obvious that maintaining such a large number of hosts is challenging; however, if the network were divided into smaller parts, it would be much simpler to maintain. For instance, if we take a class A address as an example, there are 224 possible hosts for each network. Let’s now discuss splitting a network into two parts: You must select one bit from the host ID part for each Subnet in order to divide a network into two sections.
Two Subnets can be seen in the aforementioned diagram. Because it is a class C IP, the network id part has 24 bits and the host id part has 8 bits.
Network subnetting should be carried out without affecting the network bits. The first three octets in class C remain unchanged because they are network bits.
What is an IP address?
IWe need to define IP addresses quickly in order to comprehend subnets. In order for data sent over the Internet to reach the correct device among the billions of devices connected to the Internet, each device that connects to it is given a distinct IP (Internet Protocol) address. Although IP addresses are typically written as a string of alphanumeric characters, computers read them as binary code (1s and 0s).
What do the different parts of an IP address mean?
The IPv4 addresses discussed in this section are those that are displayed as four decimal numbers separated by periods, such as 203.0.113.112. (IPv6 addresses are lengthier and contain both letters and numbers.)
Each IP address consists of two parts. The first component identifies the network to which the address belongs. The device within that network is described in the second part. Nevertheless, the “first partlength “‘s varies based on the network’s class.
Networks are divided into various classes, denoted by the letters A through E. Millions of devices can be connected by class A networks. Class B and Class C networks are getting smaller and smaller (Class D and Class E networks are not commonly used.)
Here is an explanation of how these classes influence IP address generation:
Class A network: The network is denoted by the first period, and the device within that network is denoted by everything that follows. As an illustration, the network is denoted by “203” and the device is denoted by “0.113.112.”
Class B network: Prior to the second period, the network is indicated everywhere. Again using the example of 203.0.113.112, “203.0” denotes the network and “113.112” denotes the device connected to that network.
Class C network: Everything before the third period for Class C networks indicates the network. The Class C network is denoted by “203.0.113” in the same example, and the device is denoted by “112”.
Why is subnetting necessary?
The way IP addresses are put together makes it relatively easy for Internet routers to identify the proper network to route data into, as the previous example shows. It might take some time for the data to locate the appropriate device in a Class A network, for example, where there may be millions of connected devices. Subnetting is useful because it restricts the IP address’s use to a specific set of devices.
IP addresses cannot be used to specify which subnet an IP packet should go to because they can only be used to identify the network and the device address. A device known as a subnet mask is used by routers in a network to divide data into subnetworks.