Verilink AS2000: The Basics (880-502981-001) Product Manual - Manual (Page 161)

Acronyms and Definitions
Verilink Access System 2000: Basics Glossary-41
R
RAI See remote alarm indication
(RAI) .
RAM See random access memory .
random access memory The primary memory of a
computer. Memory that can be
overwritten with new information.
read-only memory A memory device which can be
read only, not written to.
Receive data Information arriving at the local
site from the WAN.
red alarm A major alarm associated with the
complete loss of data. Three
conditions causing a red alarm are:
alarm indication signal (AIS) ,
loss of signal (LOS) , or loss of
frame (LOF) . A device in red alarm
sends a yellow alarm toward the
net.
register A circuit in a Channel Service
Unit (CSU) storing performance
data parameters retrieved by an
ASCII terminal operator or the
Node Manager . Each register can
be reset by an authorized operator
after data retrieval.
remote alarm bit Specific for E1 lines, bit 3 of
timeslot 0 (zero) in frames not
containing the frame alignment
signal. It indicates an alarm to the
remote end. A zero bit is normal
operation. A one bit is an alarm
condition.
remote alarm indication (RAI) See yellow alarm .
remote alarm indication seconds (RAIS) The number of seconds during
which a Channel Service Unit
(CSU) receives a yellow alarm .
The RAIS counts are stored by the
CSUs in AS2000 nodes.
remote alarm received Specific for E1 lines, a signal sent
to the near end to indicate that the
far end received an error
condition. (Similar to RAI in T1
lines.)