Subnet mask in computer Networks

Mar 12, 2026 • 46m • 119 views

A subnet mask is a 32-bit value used to divide an IP address into network and host portions. It consists of consecutive 1s (network bits) followed by 0s (host bits) in binary form. It is used to determine whether two IP addresses belong to the same network. Subnet masks are commonly represented in dotted decimal form (e.g., 255.255.255.0) or CIDR notation (/24). Subnetting improves efficient IP address allocation and network management, which is important for GATE CSIT.