(1) A communications device that amplifies (analog) or regenerates (digital) the data signal in order to extend the transmission distance. Available for both electronic and optical signals, repeaters are used extensively in long distance transmission. They are also used to tie two LANs of the same type together. Repeaters work at layer 1 of the OSI model. See bridge and router.

(2) The term may also refer to a multiport repeater, which is a hub in a 10Base-T network.