The IEEE has finally dotted the Ts and crossed the Is on its IEEE 802.3ab standard, known less formally as Gigabit Ethernet over copper cabling or 1000Base-T. The spec. was to have been ratified earlier this year, but a dearth of physical layer chips prevented manufacturers from shipping product. That in turn persuaded the IEEE to hang fire on final ratification until the supply situation was rectified. The new standard describes how Gigabit Ethernet communications can take place over four pairs of CAT-5 copper cabling of up to 100m in length. Gigabit Ethernet has already been defined for fibre-optic cabling, but the new spec. allows the technology to be implemented over users' existing cable infrastructures, which is likely to speed its adoption. ®