What is the main purpose of using CIDR (Classless Inter-Domain Routing)?

The main purpose of using CIDR (Classless Inter-Domain Routing) is to enable more efficient routing of IP addresses. CIDR allows for the aggregation of multiple IP addresses into a single routing table entry, which reduces the size of the routing tables in routers. This is crucial for the scalability of the internet, as it minimizes the amount of routing information exchanged between routers and leads to a more efficient use of IP addresses.

By not adhering to the rigid classful structure of traditional IP addressing, CIDR enables network administrators to create subnets of varying sizes based on actual needs rather than being restricted to predefined classes. This flexibility allows for more efficient allocation of IP address space and minimizes waste, but the primary contribution of CIDR is its ability to streamline routing processes by consolidating route information and thereby enhancing overall network performance.

While simplifying IP address management and facilitating subnetworking are benefits of CIDR, they are secondary to the primary advantage of optimizing routing efficiency. Additionally, CIDR is not specifically designed for allocating IPv6 addresses; it applies to both IPv4 and IPv6 addressing schemes.