Instruction manual

MERLIN LEGEND Communications System Release 5.0
Maintenance and Troubleshooting
555-650-140
Issue 1
June 1997
Glossary
Page GL-14
DID (Direct Inward Dialing) Service that transmits from
the telephone company central office and routes
incoming calls directly to the called extension,
calling group, or outgoing trunk pool, bypassing the
system operator.
DID trunk Incoming trunk that receives dialed digits from the
local exchange, allowing the system to connect
directly to an extension without assistance from the
system operator.
digital Representation of information in discrete elements
such as off and on or zero and one.
See also analog
transmission.
Digital Communica-
tions Protocol
See DCP.
digital data station
See ISDN terminal adapter data station .
Digital Signal 0 See DS0.
Digital Signal 1
See DS1.
digital switch
element
See DSE.
digital transmission Mode of transmission in which the information to be
transmitted is first converted to digital form and then
transmitted as a serial stream of pulses.
See also
analog transmission
.
DIP switch (dual in-line package) Switch on a 400EM module
used to select the signaling format for tie-line trans-
mission. Also used on other equipment for setting
hardware options.
direct facility
termination
(DFT)
See personal line.