CIDR (Classless Inter-Domain Routing)

CIDR, or Classless Inter-Domain Routing, is a method used to allocate and manage IP addresses more efficiently than the older class-based system. Instead of dividing addresses into fixed classes (A, B, C), CIDR allows for flexible subnetting, meaning networks can be tailored to fit varying sizes. Addresses are expressed as a combination of an IP address and a suffix (e.g., 192.168.0.0/24), where the suffix indicates how many bits are used for the network portion. This approach reduces waste of IP space and helps improve routing efficiency on the internet.