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100BASE-T -- A term for any of the three standards for 100 Mbit/s Ethernet over twisted pair cable up to 100 meters long. Includes 100BASE-TX, 100BASE-T4 and 100BASE-T2

For signal degradation and timing reasons, Ethernet segments have a restricted size which depends on the medium used.

For example, 10BASE5 coax cables have a maximum length of 500 metres (1,640 feet). A greater length can be obtained by using an Ethernet repeater, which takes the signal from one Ethernet cable and repeats it onto another cable. Repeaters can be used to connect up to five Ethernet segments, three of which can have attached devices. This also alleviates the problem of cable breakages: when an Ethernet coax segment breaks, all devices on that segment are unable to communicate; repeaters allowed the other segments to continue working.

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