Digital Link DL3800 DS1, Руководство пользователя

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Glossary G-7
G
C
CCITT
International Telegraph and Telephone Consultative Committee.
central ofÞce (CO)
The phone company switching facility or center; usually a Class 5 end ofÞce, at
which subscribers' local loops terminate.
channel
A physical or logical path allowing the transmission of information; the path
connecting a data source and receiver.
circuit
Generally referring to a transmission medium connecting two or more
electronic devices.
clear channel
A characteristic of a transmission path or digital circuit in which the full
bandwidth is available to the user. The phone company does not use any
portion of the bandwidth for framing or control bits.
clock
An oscillator-generated signal providing a timing reference for a transmission
link; used to control timing functions such as sampling interval, signaling rate
and duration of signal elements.
code conversion
The process of changing the bit grouping for a character in one code into the
corresponding bit grouping for the character in another.
CMI (Control Mode Idle)
The process of changing the grouping for a character in one code into the
corresponding bit grouping for the character in another.
communications port (Comm Port)
The electrical interface between a unit and the operatorÕs terminal. Operator
commands and responses can be communicated through the Comm Port.
connector
A physical interface, such as DB-15 or RS-232-C, typically with male or female
components.
CPE (Customer Premises Equipment)
Equipment that interfaces the telephone network and physically resides at the
user's location.