snafur
join:2004-11-05
| reply to tonydi
Re: [Line Problem] random sync loss several times a day
Thanks, tonydi. Here are the answers, in order.
The package is ATT Express. The modem is the Speedstream 5100b with 5 lights on the front. There is a Linksys WRT54GS plugged into the modem with a static ip address ...1.64. PPPoE is handled by the modem. The modem has been power cycled on occasion or just left on for the line to recover, which it always does eventually. (Indeed it has gone down a couple of times while I'm typing this.)
Normally, the first four lights (Power, Ethernet, DSL and Internet) are steady green, and the Activity light flashes when the packets flow. When the line goes down, the Power and E-net lights stay steady green, the DSL light flashes red for a while, then flashes green for a while and the Internet light goes out. Sometimes the DSL light alternates between flashing red for 5 seconds then green for 5 seconds, back and forth for several minutes (as it is now doing!) Usually, it re-syncs in about 30 seconds.
Listening to the line, it was quiet just now, but has had a slight hum, or some static on occasion (usually not at the same time.) I've checked that the other phones are plugged into the Phone port on the filters and none have been left unfiltered. And we lost Dial Tone only once that we know of. It's not effected by taking a phone off hook, either.
The line stats when it's Up are:
Line State UP
Modulation G.dmt
Data Path fast
To Modem To Internet
Max Allowed Speed (kbps) 1536 384
SN Margin (dB) 16.0 -
Line Attenuation (dB) 53.0 -
Loss of Signal 0 -
Loss of Frame 0 0
CRC Errors 2 1
Thanks for your help with this! I'll post this now while I have sync. haha. |
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tonydi
Premium,MVM
join:2001-05-11
San Jose, CA
| Since it sounds like it drops sync often it will be easier to diagnose with different tests.
Those stats don't look bad enough to drop sync unless those CRC Error numbers change drastically or the SN Margin drops down below about 6 dB. So keep an eye on that stat page and refresh it often so you can monitor those numbers.
If the regular phone service is having any issues at all, that can definitely affect the DSL connection. And you're sure you have everything connecting to the DSL telephone number filtered except the modem? I'd suggest removing everything connected to the line except the modem and see if the sync problem remains.
You might want to also try hooking the modem directly to your NID and see if the sync remains steady there.
»AT&T Southeast Forum FAQ »How do I check modem stats, synch rates & speeds at NID - Residential Housin |
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snafur
join:2004-11-05
| OK. I've removed all other equipment on the line including the filters so only the modem is plugged in. The CRC errors have jumped to 553 - 1 so I'll power cycle the modem now, too. I'll come back later and let you know how stable things are like this. Thanks for your help. |
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snafur
join:2004-11-05
| Well, that didn't last long. I power cycled the modem and it has taken about 15 minutes to get sync back. Here is the Stats page from the brief moment it was Up during that time:
Line State UP
Modulation G.dmt
Data Path fast
To Modem To Internet
Max Allowed Speed (kbps) 32 384
SN Margin (dB) 2147483647.0 -
Line Attenuation (dB) 60.5 -
Loss of Signal 0 -
Loss of Frame 0 0
CRC Errors 260 6
Now it's back to:
Line State UP
Modulation G.dmt
Data Path fast
To Modem To Internet
Max Allowed Speed (kbps) 1536 384
SN Margin (dB) 13.5 -
Line Attenuation (dB) 53.5 -
Loss of Signal 0 -
Loss of Frame 0 0
CRC Errors 12 2
I'm looking now for a 50 foot cable to run to the NID. Will that length be a problem? |
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snafur
join:2004-11-05
| Sorry if I'm posting too much info, but I did the test at the NID, and line stats aren't much different:
Line State UP
Modulation G.dmt
Data Path fast
To Modem To Internet
Max Allowed Speed (kbps) 1536 384
SN Margin (dB) 14.0 -
Line Attenuation (dB) 52.5 -
Loss of Signal 0 -
Loss of Frame 0 0
CRC Errors 2 2 |
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snafur
join:2004-11-05
| Thanks d_l. I read your response in another thread about the SN margin, too. In the meantime, I tested at the NID and all seemed OK. I could not do an extended test but the link has been stable since then. (I have connected my POTS equipment again, too, with all the filters.)
I have updated the modem software to 1.0.0.53, but when I try to use the DMT tool, all I get is a blank graph and limited data:
Downstream Maxrate (Estimated): 1536
Upstream Maxrate (Estimated): 384
Bit tones with notches/missing bits:
bit(s) 1:63 4.3125 - 276 KHz
bit(s) 65:255 280.3125 - 1104 KHz
Could this be because I'm on a Mac? I followed the instructions for saving the Tech Readout as html.
Thanks for your help. |
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