An Ethernet standard that transmits at 1 gigabit per second. Gigabit Ethernet (GbE, GE) connects PCs and servers in local networks and is commonly employed along with a mix of 10/100 Mbps devices. For example, a 10/100/1000 switch supports all three rates and adjusts to the highest speed between sender and receiver. All new computers and most network devices support Gigabit Ethernet.
GbE transmits full duplex from point to point using Ethernet switches and half duplex in a shared Ethernet hub environment (see
CSMA/CD).
IEEE 1000Base-T (802.3ab)
The 1997 standard (IEEE 802.3z) required multimode fiber or shielded copper cables, but two years later, 1000Base-T enabled GbE to run on ordinary Cat 5 copper and be readily used in existing networks. Four wire pairs each transmit 250 Mbps in both directions.
TIA 1000Base-TX
A competing standard created by the TIA that never caught on used simpler electronics but required Cat 6 cabling. However, 1000Base-T is often erroneously labeled 1000Base-TX. See
Ethernet and
10 Gigabit Ethernet.
COPPER CABLE
Encoding Cable Range
Standard Method Type (meters)
1000Base-T
802.3ab 4D-PAM5 Cat5-UTP 100
1000Base-TX
TIA/EIA-854 4D-PAM5 Cat6-UTP 100
1000Base-CX
802.3z 8B/10B Cat1-STP 25
OPTICAL CABLE
(8B/10B Encoding)
Fiber Modal
Diameter Bandwidth Range
(microns) (MHz-km) (meters)
1000Base-SX
802.3z
62.5 multimode 160 220
62.5 multimode 200 275
50 multimode 400 500
50 multimode 500 550
1000Base-LX
802.3z
62.5 multimode 500 550
50 multimode 400 500
50 multimode 500 550
9 singlemode --- 5000