Spirent SmartBits System, Reference Manual

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Chapter 11: ATM Cards
ATM Alarms
154 SmartBits System Reference
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PLCP OOF . For DS1 PLCP or E1 PLCP modes only. PLCP out of frame error
condition detected.
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PLCP LOF . For DS1 PLCP or E1 PLCP mapping modes only. PLCP loss of frame
error condition detected. This alarm condition is declared when the OOF condition
has been declared for eight consecutive frames.
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PLCP RAI . For DS1 PLCP and E1 PLCP modes only. PLCP remote alarm indication
received in the DS1 or E1 PLCP frame. This is also called a yellow alarm. This alarm
is declared when the yellow alarm bit of the G1 octet in the PLCP frame has been
active for ten consecutive frames.
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SEF . For DS1 framing mode only. Severely Errored Frame event. This bit is set to
one in DS1 framing modes when 2 of 6 Ft or FPS bits are received in error. This field
bit is not used in E1 framing modes.
ATM Alarms, AT-9025 SmartCard
In SmartWindow, select the Alarms tab from the Statistics window to display alarm
conditions for the test.
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LOS . Loss of Signal condition. The SmartCard monitors LOS conditions as follows:
– The SmartCard looks at successive groups of 204 symbols . The card's internal
counter increases by one if all 204 symbols in a group are valid and decreases by
one if even one symbol in the group is invalid.
– If an LOS condition exists (light is red), the alarm is cleared once the SmartCard
receives seven groups of 204 valid symbols and the counter increases to 7 (maxi-
mum value).
– When the alarm is in a cleared state (a signal is present), the alarm is asserted
again once the counter decreases to 0 (minimum value). The initial counter value
is 0.