In Telecommunications, T-carrier is the designation of a generic system of numerical telecommunication multiplexed in an original manner developed by Bell Labs and used in North America and with the Japan.

The basic unit in the system T-carrier is the DS0 which has a transmission of 64 kbit/s, and is usually used for a circuit voice.

The system E-carrier, where “E” means Européen, is incompatible and is used everywhere in the world apart from Japan and of the USA.

T1

This technique consists in dividing the numerical trunk of the network on two pairs of wire.

Thanks to this technique, it is possible to reach a flow of 1,544 Mbit/s in the 2 directions out of two twisted pairs. It is possible that the flow, if it is to 2 Mbit/s, can fall to 384 kbit/s seconds for example according to quality from the line and the distance from the line on the last kilometer (between 3 and 7 km following the diameter of the wire, respectively between 0.4 mm and 0.8 mm).

Circuits T2 and T3 transport several multiplexed channels T1, making it possible to reach flows up to 44,736 Mbit/s.

It is supposed that the flow of 1,544 Mbit/s. A. be empirically selected. The tests carried out by AT&T Lines Length in Chicago were carried out on buried circuits and the parts accessible located at 6600 feet one from the other. The speed of the circuit was thus increased until the rate of loss is unacceptable, then reduced.

See too

• Optical Carrier