Tier 1 Internet Service Provider (Tier 1 ISP)

Considered the highest ISP class, a tier 1 ISP has its own IP network in a particular region connected with the primary Internet backbone and/or other tier 1 ISP of same or different regions. It maintains the entire routing table for the Internet in its region.

Typically, a tier 1 ISP sells bandwidth to tier 2 and tier 3 ISPs, which, in turn, provide Internet connectivity to businesses and individual customers. Moreover, a tier 1 ISP binds an agreement with another tier 1 ISP for the free exchange of traffic and information. Thus, an ISP cannot be classified as tier 1 if it is required to pay a transit or peering fee to connect to a tier 1 ISP in the same global region.