Why Is Subnetting Important?
Subnetting is important for several reasons. • Subnetting helps to reduce the number of routes needed in a routing table. This was extremely important to the Internet. In the early days of the Internet, companies were directly assigned IP address ranges by the Internet Assigned Numbers Authority (IANA). As the Internet grew, each of the uniquely assigned ranges had to be included in the Internet routing table, and this quickly resulted in huge routing tables. At this point, IANA decided that instead of issuing IP address ranges directly to companies, it would set up regional authorities that would distribute IP addresses. These regional authorities are ARIN (North America), RIPE (Europe), LACNIC (Latin America), APNIC (Asia), and AFRINIC (Africa). Each of these agencies is assigned a large block of addresses by IANA; the agency then subnets these blocks and assigns them to the various Internet service providers (ISPs). The ISPs subnet their addresses even further and assign them to the
