Structured Cabling : Multipair Cable

Multipair cable backbone balanced twisted-pair is specified in performance categories as category 3 (specified up to 16 MHz) and category 5e (specified up to 100 MHz). 
In addition to the 800 m (2624 ft) backbone cable length for relatively low bandwidth
(< 100 MHz) voice systems, the standard includes a recommendation to limit balanced twisted pair backbones to 90 m (295 ft) for data applications. Total length between active equipment connections should not be greater than 100 m (328 ft).

Multipair Cable is used for voice and data communications, interconnection of telephone key systems, PBX and intercom systems. They are available for indoor as well as outdoor use, with different constructions and specifications. The indoor cables are offered for both plenum (CMP) and riser (CMR) applications, whereas the outdoor cables are designed for duct or direct burial applications where protection from moisture is required and aluminum shielding is desired.