ADTRAN 1202011L1, Руководство пользователя

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Appendix H. Glossary
61204011L1-1 DSU IV ESP User Manual H-3
CS
See CTS.
CSU
See channel service unit.
CTS
clear to send. A signal on the DTE interface indicating that the DCE is clear to
send data.
DBU
dial backup. Providing a secondary, switched dial service to route data upon pri-
mary link failure.
data service unit
DSU. A device designed to transmit and receive digital data on digital transmis-
sion facilities.
dB
decibel. A unit of measure of signal strength, usually the relation between a
transmitted signal and a standard signal source.
data communications equipment (DCE)
Device that provides all the functions required for connection to telephone com-
pany lines and for converting signals between telephone lines and DTE. Also see
DTE.
DDS
digital data service. A private line digital service, for transmitting data end-to-
end at speeds of 2.4, 4.8, 9.6, and 56 kbps and in some cases 19.2, 38.4, or 64 kbps.
The systems can use central hub offices for obtaining test access, bridging legs of
multipoint circuits, and cross connecting equipment. DDS is offered on an inter-
LATA basis by AT&T and on an inter-LATA basis by the Bell operating compa-
nies.
data link connection identifier (DLCI)
A unique number assigned to a PVC end point in a frame relay network. Identi-
fies a particular PVC endpoint within a user's access channel in a frame relay
network and has local significance only to that channel.