Address Terms and Definitions
Varible Length Subnet Masks (VLSM)—The ability to place a variable-length subnet mask on a single IP network number.
Supernetting—The ability to apply a mask to an IP address that is shorter than its natural mask.
Classless Inter-Domain Routing (CIDR)—An advertisement mechanism that allows for advertising routes without regard to Class assignment. The route could be identified by a supernet or by an extended subnet mask.
Address aggregation—The ability to summarize contiguous blocks of IP addresses as one advertisement.