Gigabit Ethernet is a local area network (LAN) transmission standard that provides a data rate of 1 billion bits per second (one gigabit). Gigabit Ethernet is defined in the Institute of Electrical and Electronics Engineers 802.3 standard and the first product versions of it are now available. Gigabit Ethernet is used as an enterprise backbone.

Gigabit Ethernet is carried primarily on optical fiber (with very short distances possible on copper media). Existing Ethernet LANs with 10 and 100 Mbps cards can feed into a Gigabit Ethernet backbone. An alternative technology that competes with Gigabit Ethernet is asynchronous transfer mode (ATM).

See also, 1000BaseT, 1000BaseSX , 1000BaseLX  and 1000BaseCX.