Gigabit Ethernet: 1000BASE-T

This technical paper from the 10 Gigabit Ethernet Alliance, a group of vendor companies interested in promoting the forthcoming standard, provides a comprehensive introduction to Gigabit Ethernet over four-pair 100 Ohm Category 5 cabling. The Gigabit Ethernet standards define an interface (called the GMII) to the Ethernet Media Access Control (MAC) layer, management, repeater operations, topology rules, and four physical layer signaling systems: 1000BASE-SX (short wavelength fiber), 1000BASE-LX (long wave-length fiber), 1000BASE-CX (short run copper) and 1000BASE-T (100-meter, four-pair Category 5 UTP).