（单词翻译:单击）
CPU
central processing unit
Cross Connect
1.in a premises1 distribution system, equipment used to terminate and administer communications circuits. In a wire cross connect, jumper wires or patch cords are used to make circuit connections, between horizontal and backbone2 wiring segments. 2. in transmission systems a patch panel for connecting circuits.
CSDC
circuit-switched digital capability3
CSMA/CD
Carrier sense multiple access with collision detection; a local area network contention4 based access control protocol5 technique by which all devices attached to the network "listen" for transmissions in progress before attempting to transmit themselves and, if two or more begin transmission simultaneously6, are able to detect the "collision". In that case each backs off (defers) for a variable period of time (determined by a preset algorithm) before again attempting to transmit. (Defined by the IEEE 802.3 standard).
CSR
Centrex station rearrangement
CSU
channel service unit
Customer Premises Equipment
Customer Premises Equipment is all telecommunications terminal equipment located on the customer premises. except coin operated telephones.
