Spirent SmartBits System, Справочное руководство

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Chapter 11: ATM Cards
ATM Alarms
SmartBits System Reference 151
ATM Alarms
Applications
Supported:
SmartWindow, SmartLib.
Card Types:
See specific ATM card topics.
See also: “ATM Line Event Statistics” on page 155 .
ATM Alarms, AT-9155C/9155Cs OC-3 and AT-9622/9622s OC-12c
SmartCards
In SmartWindow, select the Alarms tab from the Statistics window to display alarm
conditions for the test.
Section Alarms:
•
LOS . Loss of Signal is asserted when 20
±
3 microseconds of continuous zero
patterns have been detected. LOS is cleared when two valid framing words are
detected with no LOS condition detected in the intervening time.
•
OOF . Out of Frame is declared when 1 or more bit errors in the framing pattern of
four consecutive frames is in error. Out of frame is cleared when the A1 byte and all
A2 bytes of a SONET frame have been read error free.
•
LOF . Loss of Frame is declared when an out of frame condition is declared for 3
microseconds or longer. LOF is cleared when an in frame condition exists for 3
microseconds or longer.
Line Alarms:
•
AIS . Line Alarm Indication Signal is set when a binary 111 pattern is detected in bits
6, 7, and 8 of the K2 byte for five consecutive frames. Line AIS is cleared when a
pattern other than 111 is detected in the K2 byte for five consecutive frames.
•
FERF . The line Far End Receive Failure, also called the Remote Defect Indicator, is
set when a binary 110 pattern is detected in bits 6, 7, and 8 of the K2 byte for five
consecutive frames. Line AIS is cleared when a pattern other than 110 is detected in
the K2 byte for five consecutive frames.
•
LOP . Loss of Pointer is set whenever an invalid SONET pointer value is read from the
H1 and H2 bytes for eight consecutive frames. The Loss of Pointer is cleared when
any valid pointer value, including AIS, is received for 3 consecutive frames.