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List of terms
Nortel Multiservice Switch 7400/15000/20000
Terminology
NN10600-005 7.2S1 Standard
PCR7.2 and up March 2006
Copyright © 2006, Nortel Nortel Confidential
alarm agent
An entity residing on every function processor (FP) and control processor
(CP) that receives alarm events from a variety of services/applications.
alarm
Notification of an unusual, important, or abnormal event. An event can be
degradation of service or quality of service conditions, processing errors, out-
of-service conditions, software errors, administrative conditions, or security
violations.
alarm collector
An entity residing on the active control processor (CP) that receives alarms
from its alarm agents.
alarm indication signal (AIS)
1 A signal transmitted in lieu of the normal signal to maintain transmission
continuity and to indicate to the receiving equipment that there is a
transmission interruption located either at the equipment originating the
AIS signal or upstream of that equipment.
2 A signal transmitted in the downstream direction from a point of failure.
The AIS signal is used at the physical and ATM layers.
A-law
A technique for translating pulse code modulated voice into 64 kbit/s digital
voice channels. A-law is used in countries that use E1 function processors.
See also mu-law (page 83).
allowed cell rate
In ATM ABR networking, the rate at which the ABR source is allowed to
transmit cells into the network. The allowed cell rate for an ABR connection
varies dynamically as resource availability changes along the connection.
allowed cell rate decrease time factor (ADTF)
In ATM ABR networking, the time interval permitted between sending forward
resource management (FRM) cells before the allowed cell rate is decreased
to the initial cell rate (ICR). If the source does not transmit an
FRM cell for a period of ADTF centiseconds (hundredths of a second), it
reduces its allowed cell rate to the value of its ICR. If the allowed cell rate is
already at or below ICR, further rate reductions are defined by the ABR FRM
cell limit.
allowed information rate (AIR)
A pro-active congestion control mechanism used by the network that reduces
allocated bandwidth when congestion occurs and by doing so discards frames
in a controlled fashion.