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B-8
MAX Administration Guide
Diagnostic Parameters and Commands
Using diagnostics-related VT100 commands
Using E1-related commands
Diagnostic commands for E1 lines appear in the Net/E1 > Line Diag menu:
Net/E1
Line Diag
Line LB1
Line LB2
To execute one of the commands, select it and press Enter.
Line LB1
Line LB1 is a Line LoopBack command for Line 1in an E1 slot. When you start the line
loopback test for a E1 line, a remote device can test the E1 line and the MAX unit’s interface to
the E1 line. All signals received by the MAX are looped back (behind the MAX unit’s CSU
repeater or DSX signal-conditioning module) toward the remote device. The remote device
can determine the quality of the E1 line by comparing the sent signal to the received signal.
Line LoopBack (LLB) occurs behind the MAX unit’s CSU repeater or DSX
signal-conditioning module. Drop-and-Insert channels are also looped back. Do not activate
LLB when a call is active on the line. Doing so disrupts the data flow between the codecs
connected to either end of the network line. The MAX responds to both the inband LLB signal
and the Facility Data Link (FDL) LLB message. Therefore, a management device can put the
MAX into LLB. A management device is a unit, on an E1 line, that measures the line’s
performance and can send management signals to other devices on the line.
To initiate a loopback test on the first E1 line, highlight Line LB1 and press Enter. After
prompting for confirmation, the MAX starts the loopback test and the Alarm LED lights up.
When you exit the menu option, the MAX automatically deactivates the loopback.
Line LB2
Line LB2 is a Line LoopBack command for Line 2 in an E1 slot. When you start the line
loopback test for an E1 line, a remote device can test the E1 line and the MAX unit’s interface
to the E1 line. All signals received by the MAX are looped back (behind the MAX unit’s CSU
repeater or DSX signal-conditioning module) toward the remote device. The remote device
can determine the quality of the E1 line by comparing the sent signal to the received signal.
LLB occurs behind the MAX unit’s CSU repeater or DSX signal-conditioning module.
Drop-and-Insert channels are also looped back. Do not activate LLB when a call is active on
the line. Doing so disrupts the data flow between the codecs connected to either end of the
network line. The MAX responds to both the inband LLB signal and the Facility Data Link
(FDL) LLB message. Therefore, a management device can put the MAX into LLB. A
management device is a unit, on an E1 line, that measures the line’s performance and can send
management signals to other devices on the line.
To initiate a loopback test on the second E1 line, highlight Line LB2 and press Enter. After
prompting for confirmation, the MAX starts the loopback test and the Alarm LED lights up.
When you exit the menu option, the MAX automatically deactivates the loopback.