GBE (GigaBit Ethernet)

GBE stands for Gigabit Ethernet, which is a general term for a group of standards which allows for networking at speeds of up to one billion bits (one gigabit) per second between devices on a Local Area Network. Gigabit Ethernet can also be abbreviated as GbE or 1 GigE.

Gigabit Ethernet is one of the latest implementations of the Ethernet standard, a frame-based computer networking technology originally developed at the prolific and creative Xerox Palo Alto Research Center in the 1970’s. The name is derived from the late 19th century concept of the “luminiferous aether,” a hypothetical background medium for the universe.

Many motherboard manufacturers now fabricate models with an on-board Gigabit Ethernet port, and some higher-end boards (even at the consumer level) have two GBE ports. Among other uses, this gives the computer a redundant port in case of failure, or it can allow the computer to function as a firewall or router.

Ethernet uses a scheme referred to as carrier sense multiple access with collision detection (CSMA/CD) to allow devices to share the networking medium. Networked devices can send packets across the wire at any time, which means that collisions may occur. When a collision occurs, the computers wait a random amount of time and then attempt to re-send the data. In a high-traffic network where hubs are in use, this can cause a lot of problems, especially as the re-sent transmissions become more and more frequent. However, network switches make this much less of a problem — unless the majority of traffic has a specific port as a source or destination, such as a busy file server.

While the IEEE 802.3-2005 standard that defines GBE allows for a wide range of implementations, including half-duplex operation and the use of GBE hubs, full-duplex operation utilizing switches is the most common implementation.

The standard cabling for Gigabit Ethernet is Cat 5 UTP (unshielded twisted pair). Previous slower versions of Ethernet (10BaseT and 100BaseT, running at 10 megabits per second and 100 megabits per second respectively) utilized only two of the four pairs of wire in the cable. Gigabit Ethernet uses all four pairs (eight wires), and uses four varying levels of voltage in order to achieve the higher data rate.

Gigabit Ethernet Wiring Diagram