Lantronix
ION x6010 User Guide
33493 Rev. F
Page 238 of 261
LOS Detection
The x6010 LOS (Loss of Signal) detector monitors the amplitude of the incoming signal level and pulse
density of the received TIP/RING signals. A LOS is detected when the incoming signal has “no
transitions”. The LOS is cleared when the incoming signal has “transitions”. The x6010 LOS function is
implemented in the LIU chip, but the x6010 application software may get the LOS status via interface
with the FPGA. The x6010 LOS detection is provided via link down and link up traps and
show
commands.
T1 Error Events and Alarm Conditions
There are error events specific to T1, and alarm conditions specific to DS4 / ESF that are generated at
the system level. Basic responses include:
1.
Check all available logs and reports for related troubleshooting information.
2.
Check the x6010 NID connections (see “
Section 2: Installation and System Setup
”) at the near-end
and far-end.
3.
Check all cable runs for damaged cable, etc.
4.
Verify proper operation of other network devices.
5.
Check the x6010 NID configuration; see “
Section 4: Configuration
”.
T1 Error Events
ANSI T1.403 terminal equipment (CSU) transmits Performance Report messages towards the network
every second. The following Error Events can be reported in the Performance Report Message:
CRC Errors
– event occurs when the received CRC code does not match that CRC code calculated locally.
Severe Errors
– event occurs when two or more framing bit errors are detected in any 3 mSec window.
Alternatively, existing 2 of 4, 2 of 5, or 3 of 5 errored framing bit criteria can be used to declare a Severe
Error (SE). When a Severe Error is reported, the FE (Frame Bit Errors) count is set to 0.
Frame Bit Errors
– event occurs whenever an incorrect or unexpected framing bit is received. When a FE
error count is transmitted, the Severe Error (SE) count is set to 0.
Line Code Violations
– event occurs whenever an invalid line violation (bipolar violation) occurs.
Controlled Slip Events
– event occurs when frames are repeated or deleted at the receiving terminal to
compensate for clocking differences between the Carrier and the Terminal equipment.
D4 and ESF Alarm Conditions
The following D4 / ESF Alarm Conditions can be reported:
AIS CFA
(Alarm Indication Signal – Carrier Failure Alarm) – also known as a “Keep Alive” or “Blue Alarm”
signal; consists of an unframed all-ones signal sent to maintain transmission continuity. The AIS CFA
signal is declared when both the AIS state and Red CFA persist simultaneously.
OOF
(Out-Of-Frame) Condition – occurs whenever Network or DTE equipment senses errors in the
incoming framing pattern. Depending on the equipment, this can occur when 2 of 4, 2 of 5, or 3 of 5
framing bits are in error. A reframe clears the OOF condition.
