IPv4 Subnetting

Pv4 subnetting is the practice of dividing a single Class A, B, or C network into smaller subnetworks called subnets. This allows the network administrator to more efficiently allocate IP addresses and manage network traffic.

Each subnet has a unique network address and a range of host addresses. The subnet mask is used to divide the network into subnets and to determine the range of host addresses in each subnet.

For example, a Class C network with a default subnet mask of 255.255.255.0 can be subnetted into multiple subnets by borrowing bits from the host portion of the address. By using a subnet mask of 255.255.255.128, for instance, the network can be divided into two subnets, each with its own network address and range of host addresses.

Subnetting allows organizations to create separate logical networks within a physical network, which can improve security, reduce network congestion, and simplify network management.

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For more information on Addressing, Subnetting and other CCNA concepts, CCNA study notes available at https://www.certexams.com/cisco/ccna/study-notes-ccna.htm