IP Address Problem(1991) Address space depletion In danger of running out of classes a and B Why? Class C too small for most domains Very few class a-very careful about giving them out Class B-greatest problem Class b sparsely populated But people refuse to give it back Large forwarding tables 2 Million possible class C groups 9-26-06 Lecture 9: IP Packets9-26-06 Lecture 9: IP Packets 5 IP Address Problem (1991) • Address space depletion • In danger of running out of classes A and B • Why? • Class C too small for most domains • Very few class A – very careful about giving them out • Class B – greatest problem • Class B sparsely populated • But people refuse to give it back • Large forwarding tables • 2 Million possible class C groups