Verilink Access Manager 2000 (896-502037-001) Product Manual User Manual
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Access Manager 2000 Manual
A-7
Data Terminal
Equipment
Generally, user devices, such as terminals and computers, that connect
to data circuit-terminating equipment (DCE); they either generate or
receive data carried by the network.
DC
Direct Current.
DCE
See Data Circuit-terminating Equipment.
DDS
Dataphone Digital Service (AT&T). A private line digital service
offered with data rates typically at 2.4, 4.8, 9.6, 19.2, and 56 kbps.
Decibel (dB)
A measure of the relative strength of two signals. The number of
decibels is ten times the log of the ratio of the power of two signals or
20 times the log of the ratio of the voltage of two signals.
Digital Signal
Level 0
This term describes the signal carried on a lower than T1 speed carrier
facility, specifically, a 64 kbps rate signal.
Digital Signal
Level 1
This term describes the 1.544 Mbps digital signal carried on a T1 or
higher-order carrier facility. There are 24 DS0s in a T1 line. Each DS0
is capable of 64 kbps or 56 kbps signal transmission.
Digital Data Service
(DDS)
A digital communications service which carries data at 56 kbps.
Digital
Multiplexer/
Demulitplexer
A digital multiplexer takes several lower speed digital lines (channels)
and combines them into one faster digital line (channel/signal).
A digital demultiplexer device which takes a digital line and divides it
into several usable channels.
DIM
See Data Interface Module.
DIU
See Data Interface Unit.
DLS
See Dual-Line Shelf.
DSU
See Data Service Unit.
DS-0
See Digital Signal Level 0.
DS-1
See Digital Signal Level 1.
Term
Definition