Verilink APS 2000 T1 Line Protection (880-502411-001) Product Manual - Manual (Page 62)

Performance Monitoring
4-10 Verilink APS 2000 User Manual
Performance
Data Registers
The CSU uses the error events above to derive additional
performance data. This data is stored in registers and can be
retrieved by an Access Manager or local ASCII terminal operator.
The performance data meets the requirements of AT&T TR-54016
and ANSI T1M1.3. Verilink-defined data is also gathered and stored
for operator retrieval.
ESF Error Event An ESF error event is an extended superframe that contains at least
one CRC-6 error event or OOF event. ESF error events are used to
derive Errored Seconds, Severely Errored Seconds, Bit Error Rate,
Unavailable Signal State, Unavailable Seconds, and Bursty Errored
Seconds.
Errored Second
(ES)
An ES is a second with at least one ESF error event. However,
errored seconds are not counted when Unavailable Seconds (UASs)
are counted.
Bursty Errored
Second (BES)
A bursty errored second is a second with 2 to 319 CRC-6 error
events. Bursty errored seconds are not counted when an SES or UAS
is counted.
NOTE: Bursty Errored Seconds are referred to as Errored Seconds -
Path (ES-Ps) in the proposed ANSI T1M1.3 performance
standard.
Severely Errored
Second (SES)
An SES is a second with 320 or more CRC-6 error events, or one or
more OOF events. Severely errored seconds are not counted when
UASs are counted.
Unavailable Signal
State (UASS)
The CSU retroactively declares a UASS at the onset of 10
consecutive SESs and clears the UASS at the onset of 10
consecutively non-severely errored seconds. The UASS is
equivalent to a Failed Signal State (FSS).
Unavailable
Second (UAS)
The CSU declares a UAS for any second during which a UASS exists.
An unavailable second is equivalent to a Failed Second (FS).
Loss-of-Frame
Count (LOFC)
An LOFC is an accumulation of the number of times an LOF is
declared. A loss of frame is declared when an LOS or OOF occurs
continuously for 2 to 3 seconds, and is cleared after 10 seconds
without a LOS or OOF event.
Errored Second -
Line (ES-L)
An AMI ES-L is a second in which one or more bipolar violations are
received from the network. A B8ZS ES-L is declared when a bipolar
violation is received that is not part of a B8ZS substitution pattern.
NOTE