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Network - 100BaseX

100BaseX (sometimes written as 100 Base-X) is a function that translates between the FDDI (Fiber Distributed Data Interface)-based physical layer and the CSMA/CD-based data-link layer in a 100 100BaseVG/AnyLAN megabit per second (Mbps) Ethernet proposed by Grand Junction Networks. The term was used more generally to refer to a 100 Mbps Ethernet developed by Grand Junction, among others. This proposed specification has since become known as Fast Ethernet, and has been refined into three variants: n 100BaseFX, which runs over fiberoptic cable n 100BaseT4, which runs over unshielded twisted pair (UTP) cable rated at Category 3 or higher-provided there are four available wire pairs n 100BaseTX, which runs over Category 5 UTP cable These variants all use the standard CSMA/CD (carrier sense multiple access/ collision detection) medium access scheme used by classic Ethernet. (In contrast, the 100BaseVG variant proposed by Hewlett- Packard and other companies uses a demand priority access scheme.) Specifications and standards for the Fast Ethernet versions have been debated by the IEEE 802.3u subcommittee, and were just approved in June 1995. BROADER CATEGORY Ethernet SEE ALSOf Fast Ethernet COMPARE 100BaseVG