In CIDR, a group of IP networks is treated as what?

In Classless Inter-Domain Routing (CIDR), a group of IP networks is treated as a single entity for the purpose of IP address allocation and routing. This is a fundamental aspect of CIDR, which allows for more efficient use of IP addresses by aggregating multiple networks into a single routing table entry.

By combining these networks under one address prefix, CIDR reduces the size of routing tables on routers, promoting more efficient routing and reducing the overall complexity of the network structure. This aggregation means that rather than managing each individual network separately, it can be dealt with as one larger block, streamlining routing processes and minimizing the potential for errors or confusions in managing numerous smaller networks.

This method contrasts with traditional class-based addressing, where routing could become cumbersome due to the need to keep track of many smaller networks. Consequently, the concept of treating a group of networks as a single entity enables significant improvements in routing efficiency and address space management.