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.
Last updated: 1995-01-30
channel service unit/data service unit
(CSU/DSU, or "..digital..") A device that performs both the channel service unit (CSU) and data service unit (DSU) functions. The Channel Service Unit (CSU) is used to terminate a DS1 or DS0 (56/64 kb/s) digital circuit. It peforms line conditioning, protection, loop-back and timing functions. The Data Service Unit (DSU) terminates the data circuit to the Data Terminal Equipment (DTE) and converts the customer's data stream into a bi-polar format for transmission.
Last updated: 2001-10-19
channel service unit ♦ channel service unit/data service unit
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