Gigabit Ethernet is a transmission technology based on the Ethernet frame format and protocol - Gigabit provides a data rate of 1000 Mbps (1 billion bits per second).

Gigabit ethernet is used to allow the fast transmission of data within local area networks (LAN's) - as Gigabit requires specific equipment such as switches & network cards, it is more commonly used to provide a network backbone.

A Gigabit backbone allows for extremely fast communication between for example network servers or between buildings/floors - existing Ethernet LANs with 10 and 100 Mbps cards will then feed into the Gigabit Ethernet backbone.

Gigabit Ethernet is carried primarily on optical fiber but can also operate using Cat5E copper cables over shorter distances - Gigabit equipment is becoming more widely used as equipment costs continue to reduce. A newer standard, 10-Gigabit Ethernet, is now also becoming available.

Gigabit Ethernet is defined in the IEEE 802.3 standard