CIDR had a rather inauspicious beginning; it was originally designed as yet another in the IETF's bag of short-term tricks to buy time for IPv6 to be developed. It's been successful beyond its developers' imagination. CIDR has not only successfully staved off address space depletion, but it has also enabled Internet routing to become much more efficient through a greater degree of aggregation. This efficiency simply was not possible under Classical IP rules. For all its benefits, CIDR was less revolutionary than might be suspected. It was directly based on VLSM and, for that reason, was readily understood and accepted by the Internet community. |