A. A Tier 1 Carrier is an ISP group possessing a world-scale broadband IP backbone, capable of controlling its own network and does not depend on an "upper" provider to maintain its quality.

Tier 1 providers have their own coast-to-coast backbone. They also have peering relationships with most of the other Tier 1 providers. Tier 2 providers get access from Tier 1 providers, but they usually have to pay for the access (which is different from the free "peering" relationships Tier 1 providers have). Tier 3 providers generally specialize in a regional presence.

The main criteria of a Global Tier 1 carrier:

• Global network reach
• Connected to all other Tier 1’s
• Have settlement-free peering with all Tier 1’s
• Connected to many customers