The Internet backbone was the central network that linked all the parts of the Internet together. The term is now used as a loose term to describe the core of the current Internet.

=History=

The original Internet backbone was the ARPANET.

In 1989 the NSFNet backbone was established, the US military broke off as a separate MILNET network, and the ARPANET was shut down.

A plan was then developed for first expanding NSFNet further, prior to rendering it obsolete by creating a new network architecture based on decentralized routing.

With the decommissioning of the NSFNet Internet backbone network on April 30, 1995, the Internet now consists entirely of the various commercial Internet service providers and private networks (as well as inter-university networks), as connected at their Peering points.

The term Internet backbone is now sometimes loosely used to refer to the inter-provider links and peering points. However, with the universal use of the Border Gateway Protocol routing protocol, the Internet functions with no single central network at all.

With the advent of the network was decomissioned in its entirety. This was a successful test of the level of fault-tolerance and redundancy of the Internet.

=Overview=

The Internet backbone consists of many different computer networks. Usually, the term is used to describe large networks that inter-connect with each others and have individual ISPs as clients. For example, a local ISP may provide service for a single town, and connect to a regional provider which has several local ISPs as client. This regional provider connects to one of the backbone networks, which provides nationwide or worldwide connections.

These backbone providers usually provide connection facilities in many cities for their clients, and they themselves connect with other backbone providers at Internet Exchange Points such as MAE-East in New York or FreeIX in France.

Backbone networks are usually commercial, educational or government owned, such as military networks. Some large companies that provide backbone connectivity include MCI, UUNET, British Telecom, AT&T and Teleglobe.

=See also=