Classful Routing

Classful routing is an early method used by computer networks to organize and identify IP addresses into fixed categories called classes (A, B, C, D, E). Each class has a specific range of addresses and default network sizes, simplifying routing decisions. For example, Class A addresses are for large networks, while Class C addresses are for smaller ones. Routers use these classes to quickly determine where to send data packets without detailed subnetting. Although largely replaced by more flexible methods today, classful routing laid the foundation for modern IP routing and network organization.