Definition of 1000BaseT in The Network Encyclopedia.

What is 1000BaseT?

A type of standard for implementing Gigabit Ethernet networks. The T in 1000BaseT identifies it as an extension of the traditional 10BaseT and 100BaseT Ethernet technologies for transmission over copper unshielded twisted-pair (UTP) cabling. Gigabit Ethernet standards are defined in the 802.3z and 802.3ab standards of Project 802 developed by the IEEE.

1000BaseT technologies are in the beginning stages of being widely implemented in enterprise-level networks. They are primarily used for short, high-speed interconnects within wiring closets and for connecting high-speed workstations to wiring closets.

Graphic 0-10. A 1000BaseT network.

How It Works

1000BaseT is an extension of standard Ethernet technologies to gigabit-level network speeds. 1000BaseT is normally implemented using the commonly installed category 5 cabling or enhanced category 5 cabling version of UTP cabling. 1000BaseT uses all four pairs of wires in standard UTP cabling, as opposed to the two pairs of wires used in 10BaseT and 100BaseT networks.

Using all four pairs of UTP cabling has certain associated problems because of attenuation, crosstalk, and echoes arising from full-duplex transmission over single wires. The 802.3ab standards specify special filters for hybrid circuits used in full-duplex transmission over single wires, a special five-level pulse amplitude modulation (PAM) encoding mechanism instead of binary signals, forward error correction techniques, and pulse shaping technologies to make 1000BaseT a functional and reliable networking technology.

Cable segments for 1000BaseT have a maximum length of 100 meters. 1000BaseT is intended mainly for connecting high-speed hubs, Ethernet switches, and routers together in wiring closets; for switch-switch connections in backbones; for switch-server connections; and for horizontal cable runs to high-speed workstations.


1000BaseT is intended to provide the simplest upgrade path for legacy 10BaseT and 100BaseT Ethernet networks.