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What Does 100BASE-T Mean?

100BASE-T is an enhanced form of Ethernet 10BASE-T and a network standard used for fast data transfer rates up to 100 Mbps. 100BASE-T is 10 times faster than standard Ethernet and, like standard Ethernet, it follows the Carrier Sense Multiple Access/Collision Detection (CSMA/CD) technique to avoid collision.


100BASE-T is an official IEEE 802.3u standard that is used to connect nodes when establishing a local area network. In 1998, 100BASE-T’s signal speed was superseded by Gigabit Ethernet.

100BASE-T is officially known as fast Ethernet.

Techopedia Explains 100BASE-T

Smart network administrators always use multi-adapter network switches and hubs that simultaneously support 10BASE-T and 100BASE-T. 100BASE-T is used primarily with star topology because it requires a centralized hub, which is used for port communication.

100BASE-T has three major standard versions in copper and fiber mediums:

  1. 100BASE-TX: Used for full-duplex point-to-point communication with two twisted cable pairs. One pair receives signals while the other sends them. 100BASE-TX uses an RJ-45 cable for physical connection and supports segment lengths of up to 100 meters.
  2. 100BASE-T4: One of the earliest Fast Ethernet versions. It uses CAT-3 twisted pair cables, and requires four cable pairs for communication. One pair receives and one pair sends signals. The two remaining pairs are reserved and used as required.
  3. 100BASE-FX: This optical fiber cable standard uses thin infrared light wavelengths for communication via two twists of cable. The two strands are used to transmit and receive signals; one sends and the other receives to provide full-duplex communication. 100BASE-FX allows for a distance of up to six miles between two stations. A repeater is required every 165 yards over long haul distances.

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Margaret Rouse

Margaret jest nagradzaną technical writerką, nauczycielką i wykładowczynią. Jest znana z tego, że potrafi w prostych słowach pzybliżyć złożone pojęcia techniczne słuchaczom ze świata biznesu. Od dwudziestu lat jej definicje pojęć z dziedziny IT są publikowane przez Que w encyklopedii terminów technologicznych, a także cytowane w artykułach ukazujących się w New York Times, w magazynie Time, USA Today, ZDNet, a także w magazynach PC i Discovery. Margaret dołączyła do zespołu Techopedii w roku 2011. Margaret lubi pomagać znaleźć wspólny język specjalistom ze świata biznesu i IT. W swojej pracy, jak sama mówi, buduje mosty między tymi dwiema domenami, w ten…