DS-3

In telecommunications, T-carrier, sometimes abbreviated as T-CXR, is the generic designator for any of several digitally multiplexed telecommunications carrier systems originally developed by Bell Labs and used in North America, Japan, and Korea.

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

The E-carrier system, where 'E' stands for European, is incompatible with the T-carrier and is used at most places in the world outside of North America, Japan, and Korea. It typically uses the E1 line rate and the E3 line rate. The E2 line rate is less commonly used. See the table below for bandwidth comparisons.