Tahoe 4681, Руководство пользователя

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Tahoe 4681 (4-port G.shdsl.bis/FastEthernet modem card)
Appendix A, Troubleshooting
Problem Possible solutions
The modems cannot
synchronize with each other
check the cables and connector pinouts
check if the speed setting is the same on both modems
check if one modem is set as Master and the other one as
Slave
the line may be too long for selected speed – lower the
speed setting on both modems
The modems are synchronized,
but no data flows
if transparent bridge is required – check if it is enabled·
check if the Noise Margin (Signal/Noise Ratio) is greater
or equal to 6 dB – decrease the line throughput if it the
NMR is too low
check the LAN cables
issue mii reset command to reset the Ethernet interface
The data isn’t transferred at
full speed or the throughputs
are asymmetrical (higher in
one direction and lower in the
other direction) check if the Noise Margin (Signal/Noise Ratio) is greater
or equal to 6 dB – decrease the line throughput if it the
NMR is too low
ensure that the modem and the LAN device on the other
end of the cable has the same Ethernet interface setting
– either autonegotiation, or forced mode
The modems loose
synchronization from time to
time
check if the Noise Margin (Signal/Noise Ratio) is greater
or equal to 6 dB – decrease the line throughput if it the
NMR is too low
try to change the leased line or at least some sections of it
– there may be loose connectors, damaged insulation or
other transient problems with the line
telecom line consists of two twisted wires – ensure that
both wires of a twisted pair are connected to pins of the
same line