channel service unit

(CSU) A type of interface used to connect a terminal or

computer to a digital medium in the same way that a modem is

used for connection to an analogue medium.

A CSU is provided by the communication carrier to customers

who wish to use their own equipment to retime and regenerate

the incoming signals. The customer must supply all of the

transmit logic, receive logic, and timing recovery in order to

use the CSU, whereas a digital service unit DSU performs

these functions.

(1995-01-30)