Subnetting in Networking

Subnetting is a process in networking used to divide a larger network into smaller, more manageable subnetworks or subnets. This technique enhances routing efficiency, improves network security, and better manages IP address allocation.

CONCEPTS OF SUBNETTING:

1.IP Address: An IP address consists of two parts: Network portion and a Host portion.

Subnetting involves modifying the division between these parts to create more network segments.

2.Subnet Mask: A subnet Mask is used to determine which part of an IP address is the network portion and which part is the host portion. It does this by masking out the network part of the address with the series of consecutive 1's(binary) and the host part with consecutive 0's.

3.CIDR Notation: Classless Inter-Domain Routing(CIDR) notation simplifies the representation of subnet masks. For example, /24 means the first 24 bits of the IP address are the network portion, and the remaining bits are for hosts.

BENEFITS OF SUBNETTING:

1.Improved Network Performance: By reducing the size of broadcast domains, subnetting minimizes unnecessary traffic and potential congestion.

2.Enhanced security: Subnetting allows network administrators to isolate sensitive parts of a network, reducing the risk of unauthorized access or data breaches.

3.Efficient IP Address Utilization: Subnetting allows for the flexible allocation of IP addresses, preventing waste and ensuring efficient use of the address space.

4.Simplified Network Management: Smaller, organized subnets make managing and troubleshooting networks easier.

WORKING OF SUBNETTING:

1.Determine Requirements: Define the number of subnets needed and the number of hosts per subnet.

2.Choose Subnet Mask: Based on the requirements, select a subnet mask that accommodates the number of required subnets and hosts.

3.Calculate Subnets: Divide the original network address using the chosen subnet mask, resulting in multiple subnets.

4.Assign IP Addresses: Each subnet can then be assigned a range of IP addresses for it's hosts.

EXAMPLE:

Suppose you have a network with the address 192.168.1.0, which provides 256 IP addresses(254 usable for hosts). To create 4 subnets, you need to reserve additional bits for the subnetting:

**Original subnet mask: 255.255.255.0

**New subnet mask: 255.255.255.192(reserving 2 more bits for subnets)

This configuration results in :

4 subnets: 192.168.1.0,

192.168.1.64

192.168.1.128

192.168.1.192

*Each subnet has 64 IP addresses(62 usable for hosts).

*Subnetting is a powerful tool for network design and management, allowing for efficient use of IP addresses, and enhanced security. Properly implemented, subnetting can significantly improve the functionality and scalability of a network.