Advantages and Disadvantages of Subnetting

What is Subnetting?

Subnetting is a process of separating a single physical network into several logical subnetworks (subnets).

  • A network segment and a host segment make up an IP address subnets formed by extracting bits from an IP address's host component and establishing several smaller sub-networks within a more extensive network.

  • Subnetting enables a business to expand its network without securing a new network number from its Internet Service Provider (ISP). Subnetting reduces network traffic while also hiding network complexity.

  • Subnetting is required when a single network number must be distributed across multiple parts of a local area network.

  • Subnets were created to alleviate the scarcity of IP addresses on the Internet.

  • A subnet mask is part of every IP address. The subnet mask known as the default subnet mask is included in all class types. The subnet mask specifies the kind and amount of IP addresses required for a specific local network. The default gateway is the firewall or router.

The following is the default subnet mask −

  • is the class A address.

  • is the class B address.

  • is the class C address.

A network administrator can subnet a single Class A, Class B, or Class C network number into smaller portions via subnetting. Subnets can be subnetted again to create sub-subnets.

Advantages of Subnetting

Some of the benefits of partitioning a network into subnets are as follows −

  • It reduces network traffic by lowering the number of broadcasts sent out.

  • It helps overcome limitations in a local area network (LAN), such as the maximum number of allowed hosts.

  • It allows people to connect to a work network from their homes without having to open the entire network.

  • It protects one network from the intrusion of another. For example, the Developer department's code must not be accessible by any other department in an organization.

  • Some subnets may require higher network priority than others. A sales department, for example, may need to host webcasts or video conferences.

  • Maintenance is simple in the case of small networks.

Disadvantages of Subnetting

Subnetting has certain drawbacks in addition to its benefits −

  • To reach a Process in a single network, there are only three steps −

    • Source Host to Destination Network,

    • Destination Network to Destination Host, and then

    • Destination Host to Process.

  • Subnetting, on the other hand, necessitates four phases for Inter Network Communication. The steps are −

    • Source Host to Destination Network,

    • Destination Network to appropriate Subnet,

    • Subnet to Host, and finally,

    • Host to Process.