Alcatel-Lucent 9500 MXC, User Manual, Page: 875 / 916

3DB 23063 ADAA - Rev 004 July 2007 1
Glossary
This section defines terms and acronyms used in the 9500 MXC documentation.
1+1 protected system
Two ODUs and two IDUs are used at each end of a link to protect against transmission failure. If a data
transmission fails on the operating ODU/IDU, it is transferred to the backup ODU/IDU.
1U
Standard EIA Rack Unit (44 mm / 1.75 in.)
4U
Standard EIA Rack Units (177 mm / 7.0 in.)
AACS
Access and Administration Control System
ADC
analog-to-digital converter
A device that converts an analog signal to a digital signal that represents equivalent information.
Address
The unique number ID assigned to one host or interface in a network.
AGC
automatic gain control voltage
A process that automatically adjusts gain as a function of a specified parameter, such as received signal level.
AIS
Alarm Indication Signal
The code generated by a regenerator upon loss of input signal or loss of frame. To prevent generation on
unnecessary alarms, the line AIS signal will maintain operation of the downstream regenerators.
ALC
Automatic Level Control
ALM
Alarm
alternate mark inversion (AMI) signal
A pseudoternary signal, representing binary digits. Successive marks are of alternately positive and negative
polarity and the absolute values of their amplitudes are normally equal. Spaces are of zero amplitude.
AMI