Why Use CIDR?

Before CIDR technology was developed, Internet routers managed network traffic based on the class of IP addresses. In this system, the value of an IP address determines its subnetwork for the purposes of routing.

CIDR is an alternative to traditional IP subnetting that organizes IP addresses into subnetworks independent of the value of the addresses themselves. CIDR is also known as supernetting as it effectively allows multiple subnets to be grouped together for network routing.