A subnet allows you to separate the flow of network traffic between hosts based on a network configuration. By organizing hosts into logical groups, subnetting can improve network security and performance.
Subnet Mask – Explained
Perhaps the most recognizable aspect of subnetting is the subnet mask. Like IP addresses, a subnet mask contains four bytes (32 bits) and is often written using the same dot-decimal notation. For example, here is a common subnet mask in its binary representation:
This subnet mask is usually displayed in the equivalent, more readable form:
A subnet mask does not function like an IP address, nor does it exist independently of IP addresses. Instead, subnet masks accompany an IP address, and the two values work together. Applying the subnet mask to an IP address splits the address into two parts, an extended network address and a host address.
