A Tier 2 Network is an Internet service provider who engages in the practice of peering with other networks, but who still purchases IP transit to reach some portion of the Internet.
Tier 2 providers are the most common providers on the Internet as it is much easier to purchase transit from a Tier 1 network than it is to peer with them and then attempt to push into becoming a Tier 1 carrier.
The term Tier 3 is sometimes also used to describe networks who solely purchase IP transit from other networks (typically Tier 2 networks) to reach the Internet.
Famous quotes containing the word network:
“Of what use, however, is a general certainty that an insect will not walk with his head hindmost, when what you need to know is the play of inward stimulus that sends him hither and thither in a network of possible paths?”
—George Eliot [Mary Ann (or Marian)