Specifications

Installation and Operation Manual Chapter 6 Troubleshooting and Diagnostics
IPmux-8/16 Ver. 6.00 Monitoring IPmux-8/16 Performance 6-13
Table 6-5. CT3 Statistic Parameters
Alarm Description
LOS The LOS defect is declared upon observing 175 +/- 75 contiguous pulse positions with no pulses of either
positive or negative polarity. The LOS defect is terminated upon observing an average pulse density of at least
33% over a period of 175 +/- 75 contiguous pulse positions starting with the receipt of a pulse.
LOF T3 Loss of Frame (LOF) failure is declared when the T3 OOF defect is consistent for 2 to 10 seconds. The T3
OOF defect ends when reframe occurs. The LOF failure is cleared when the OOF defect is absent for 10 to
20 seconds.
RAI The Remote Alarm Indication (RAI) failure is declared after detecting the Yellow Alarm Signal on the alarm
channel. The Remote Alarm Indication failure, in C-bit Parity T3 applications, is declared as soon as the
presence of either one or two alarm signals are detected on the Far End Alarm Channel. The Remote Alarm
Indication failure may also be declared after detecting the far-end SEF/AIS defect. The Remote Alarm
Indication failure is cleared as soon as the presence of the any of the above alarms are removed.
Also, the incoming failure state is declared when a defect persists for at least 2-10 seconds. The defects are
the following: Loss of Signal (LOS), an Out of Frame (OOF) or an incoming Alarm Indication Signal (AIS). The
failure state is cleared when the defect is absent for less than or equal to 20 seconds.
AIS The AIS is framed with "stuck stuffing." This implies that it has a valid M-subframe alignments bits, M-frame
alignment bits, and P bits. The information bits are set to a 1010 sequence, starting with a one (1) after each
M-subframe alignment bit, M-frame alignment bit, X bit, P bit, and C bit. The C bits are all set to zero giving
what is called "stuck stuffing." The X bits are set to one. The T3 AIS defect is declared after E3/T3 AIS is
present in contiguous M-frames for a time equal to or greater than T, where 0.2 ms ≤ T ≤ 100 ms.
The T3 AIS defect is terminated after AIS is absent in contiguous M-frames for a time equal to or greater than
T.
The T3 binary content of the AIS is nominally a continuous stream of ones.
When receiving AIS, the SYNC LED turns off.
LES Line Errored Second is a second in which one or more CV occurred or one or more LOS defects.
PES P-bit Errored Seconds. An PES is a second with one or more PCVs OR one or more Out of Frame defects or a
detected incoming AIS. This counter is not incremented when UASs are counted.
PSES P-bit Severely Errored Seconds. PSES is a second with 44 or more PCVs or one or more Out of Frame defects
or a detected incoming AIS. This counter is not incremented when UASs are counted.
CES C-bit Errored Seconds. An CES is a second with one or more CCVs or one or more Out of Frame defects or a
detected incoming AIS. This counter is not incremented when UASs are counted.
CSES C-bit Severely Errored Seconds. CSES is a second with 44 or more CCVs OR one or more Out of Frame
defects or a detected incoming AIS. This counter is not incremented when UASs are counted.
SEFS Severely Errored Framing Seconds. A SEFS is a second with one or more Out of Frame defects or a detected
incoming AIS. This counter is not incremented when UASs are counted.
UAS Number of Unavailable Seconds in the current interval.
The line becomes unavailable if 10 consecutive PSESs appear. The 10 PSESs are included in the UAS time.
The link becomes available if 10 consecutive seconds pass with no PSESs. The 10 seconds with no PSESs are
excluded from the UAS.