Gigabit Ethernet, a transmission technology based on the Ethernet frame format and protocol used in local area networks (LANs), provides a data rate of 1 billion bits per second (one gigabit). Gigabit Ethernet is defined in the IEEE 802.3 standard and is currently being used as the backbone in many enterprise networks.
Gigabit Ethernet is carried primarily on optical fibre (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 ATM. A newer standard, 10 Gigabit Ethernet, is also becoming available.
10 Gigabit Ethernet (10GBASE-T), being standardised in IEEE 802.3a, is a telecommunication technology that offers data speeds up to 10 billion bits per second. Built on the Ethernet technology used in most of today's local area networks (LANs), 10 Gigabit Ethernet is described as a "disruptive" technology that offers a more efficient and less expensive approach to moving data on backbone connections between networks while also providing a consistent technology end-to-end. Using optical fibre, 10 Gigabit Ethernet can replace existing networks that use ATM switches and SONET multiplexers on an OC-48 SONET ring with a simpler network of 10 Gigabit Ethernet switches and at the same time improve the data rate from 2.5 Gbps to 10 Gbps.
10 Gigabit Ethernet is expected to be used to interconnect local area networks (LANs), wide area networks (WANs), and metropolitan area networks (MANs). 10 Gigabit Ethernet uses the familiar IEEE 802.3 Ethernet media access control (MAC) protocol and its frame format and size. Like Fast Ethernet and Gigabit Ethernet, 10 Gigabit Ethernet uses full-duplex transmission, which makes possible a considerable distance range. On multimode fibre, 10 Gigabit Ethernet will support distances up to 300 meters; on single mode fibre, it will support distances up to 40 kilometers. Smaller Gigabit Ethernet networks can feed into a 10 Gigabit Ethernet network. (This information courtesy of Whatis.com.)