Tier 1 network

The most widely quoted source for identifying Tier 1 networks is published by Renesys Corporation, but the base information to prove the claim is publicly accessible from many locations, such as the RIPE RIS database,[6] the Oregon Route Views servers, Packet Clearing House, and others.

The subset representing Tier 1 networks is collectively understood in a loose sense, but not published as such.

New Tier 1 ISPs and their peering agreements supplanted the government-sponsored NSFNet, that program being officially terminated on April 30, 1995.

A bilateral private peering agreement typically involves a direct physical link between two partners.

This is not largely a technical issue but a commercial matter in which a financial dispute is fought out using the other party's customers as hostages to obtain a better negotiating position.

[11][12] Lower tier ISPs and other parties not involved in the dispute may be unaffected by such a partition as there exist typically multiple routes onto the same network.

[13] More appropriately then, peering means the exchange of an equitable and fair amount of data-miles between two networks, agreements of which do not preclude any pay-for-transit contracts to exist between the very same parties.

[16] While most of these Tier 1 providers offer global coverage (based on the published network map on their respective public websites), there are some which are restricted geographically.

However these do offer global coverage for mobiles and IP-VPN type services which are unrelated to being a Tier 1 provider.

A typical scenario for this characteristic involves a network that was the incumbent telecommunications company in a specific country or region, usually tied to some level of government-supported monopoly.

[51] This is a list of networks that are often considered and close to the status of Tier 1, because they can reach the majority (50+%) of the internet via settlement-free peering with their global rings.