Alcatel-Lucent 1643 AMS Operation Manual page 348

Glossary
Administrative-Unit Pointer (AU PTR)
Indicates the phase alignment of the VC-n with respect to the STM-N frame. The pointer
position is fixed with respect to the STM-N frame.
Administrator
See ITM-SC System Administrator.
AITS
→
"Acknowledged Information Transfer Service" (p. GL-1)
Alarm
The notification (audible or visual) of a significant event. See also Event.
Alarm Indication Signal (AIS)
Code transmitted downstream in a digital network that shows that an upstream failure
has been detected and also alarmed if the upstream alarm has not been suppressed.
Alarm Severity
An attribute that defines the priority of the alarm message. The way in which alarms are
processed depends on their severity.
Aligning
Using a pointer to indicate the head of a virtual container, for example, to create an
Administrative Unit (AU) or a Tributary Unit (TU).
ALS
Automatic Laser Shutdown
Alternate Mark Inversion (AMI)
A line code that employs a ternary signal to convert binary digits. In this line code
successive binary ones are represented by signal elements that are normally of
alternately positive and negative polarity but are equal in amplitude, binary zeros are
represented by signal elements that have zero amplitude.
American Standard Code for Information Interchange (ASCII)
A standard 8-bit code that is used to exchange information among data processing
systems and associated equipment.
Anomaly
A difference between the actual and the desired operation of a function.
ANSI
American National Standards Institute
APS
Automatic Protection Switching
AS
Alarm Suppression assembly
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GL-2 Alcatel-Lucent - Proprietary
See notice on first page
365-312-803R7.2
Issue 4, May 2007