TSB Address space exhaustion(1/3) Rate and scale of Internet growth was underestimated In 1970s, 32-bit address space was thought to be adequate for long term Class system(A, B, C) Internet routing is closely tied to the separation of routing within a network and routing between networks4 TSB Address space exhaustion (1/3) • Rate and scale of Internet growth was underestimated • In 1970’s, 32-bit address space was thought to be adequate for long term • Class system (A, B, C) • Internet routing is closely tied to the separation of routing within a network and routing between networks