GL-1
9161-A2-GH30-20
September 1997
Glossary
Alarm Indication Signal. A signal transmitted instead of the normal signal to continue
transmission continuity and to indicate to the receiving terminal that a transmission fault
exists at either the transmitting terminal or upstream of the transmitting signal. Sometimes
referred to as Blue Alarm.
Alternate Mark Inversion. A line encoding technique and a bipolar return-to-zero signal.
Application Module.
American Wire Gauge.
Bursty Error Seconds. A second in which more than one, but less than 320 CRC6 error
events, have occurred.
Bipolar Violation. A modified bipolar signaling method in which a control code is inserted
into the original data format.
Bipolar with Eight Zero Substitution.
Communications port. A computer’s serial communications port used to transmit to and
receive data from a DCE. The DCE connects directly to this port.
D
evice software that sets specific operating parameters for the access unit. Sometimes
referred to as straps.
Cyclic Redundancy Check. A method of error detection.
Controlled Slip Seconds. A period in which a frame was added or deleted because of a
variance in timing.
Channel Service Unit. Protects the T1 line from damage and regenerates the T1 signal.
Data Communications Equipment.
Direct Inward Dialing.
Dial Pulse Originating.
Dial Pulse Terminating.
Data Service Unit. Data communications equipment which transmits digital data over a
private line. Also used for limited distance communications over the local area network
when a high-speed modem is not needed.
Digital Signal Cross Connect level 1. An interconnection point for terminals, multiplexers
and transmission facilities.
Digital Signal level 0. A signal of worldwide standard speed for PCM digital voice channels
running at 64 kbps.
Digital Signal level 1. A signal of 1.544 Mbps in North America.
Data Terminal Equipment.
Dual Tone Multifrequency. The basis of operation for a pushbutton telephone.
AIS
AMI
APM
AWG
BES
BPV
B8ZS
COM port
configuration option
CRC
CSS
CSU
DCE
DID
DPO
DPT
DSU
DSX-1
DS0
DS1
DTE
DTMF
