ZyXEL Communications IES-612-51A User Manual

 Chapter 52 ADSL Commands

IES-612-51A User’s Guide

Syntax:

  ras> adsl linediag setselt <port number>

This command has the IES-612-51A perform a single end line test on the specified port. This 
test checks the distance to the subscriber’s location.

"

The port must have an open loop. There cannot be a DSL device, phone, fax 
machine or other device connected to the subscriber’s end of the telephone 
line.

The test takes at least 15 seconds. You can run the 

 to check 

the status of the test and to look at the results.

The following example starts a SELT test on DSL port 1.

snrm: 

This is the upstream and downstream Signal-to-Noise Ratio Margin (in dB). A 
DMT sub-carrier’s SNR is the ratio between the received signal power and the 
received noise power. The signal-to-noise ratio margin is the maximum that the 
received noise power could increase with the IES-612-51A still being able to 
meet its transmission targets.

attndr:

This is the upstream and downstream Attainable Net Data Rate (in bit/s).

farEndActatp: 

This is the upstream and downstream Far End Actual Aggregate Transmit 
Power (in dBm)

i                

This is the index number of the DMT sub-carrier.

li.rl   

The channel characteristics function is represented in linear format by a scale 
factor and a complex number. This is the real part of the complex number used 
in producing the channel characteristics function for this sub-carrier.

li.im   

The channel characteristics function is represented in linear format by a scale 
factor and a complex number. This is the imaginary part of the complex number 
used in producing the channel characteristics function for this sub-carrier

log

This is a format for providing channel characteristics. It provides magnitude 
values in a logarithmic scale. It is measured in dB. This can be used in 
analyzing the physical condition of the DSL line.

QLN

The Quiet Line Noise for a DMT sub-carrier is the rms (root mean square) level 
of the noise present on the line, when no DSL signals are present. It is 
measured in dBm. The QLN can be used in analyzing crosstalk.

SNR

This is the upstream and downstream Signal-to-Noise Ratio (in dB). A DMT 
sub-carrier’s SNR is the ratio between the received signal power and the 
received noise power. The SNR can be used in analyzing time dependent 
changes in crosstalk levels and line attenuation (such as those caused by 
temperature variations and moisture).

Table 97   Line Diagnostics Get 992.3 Command (continued)

Figure 250   SELT Diagnostic Set Command Example

ras> adsl linediag setselt 1