floppy1876
join:2004-04-04
Stockton, CA
| [Line Problem] DSL connection issues
I’ve had my DSL for 3.5 months at a new location and have noticed that I’m being disconnected quite a bit. Typically it would occur Friday night or Saturday morning but as of late its gotten more frequently and is happening every 2 to 3 days. I assumed that it was my DSL modem going bad (Speedstream 5100B) and replaced the modem with the current Motorola 2210 but that same disconnects continue to occur. I was doing my PPPOE authentication through my Linksys WRT54GL router but switched to having the DSL modem to perform the PPPOE authentication and the same disconnects still occur. After each disconnect when looking at the connection information page in the modem it states that my PAP authentication connection failed. I’ve contacted AT&T customer support and they performed some line tests and state that everything appears to be good. Any help would be greatly appreciated in resolving this issue.
1) Which AT&T DSL Package do you have –
Basic (768kbps down), Express (1.5Mbps down), Pro (3.0Mbps down), Elite (6.0Mbps down)
Elite (6.0Mbps down, 768kbps up)
2) Which modem brand and model do you have? (if Speedstream 5100, does it have 4 or 5 lights)
Motorola 2210
3) Are you using a router? If so, provide the brand and model.
Linksys WRT54GL
4) Is your PPPoE login info (username & password) entered in the modem, in your router or do you use PPPoE software?
PPOE is done via the DSL Modem
5) Describe the lights on the modem when the trouble occurs.
Internet light goes out and sometimes the DSL sync light turns red.
6) Confirm that you’ve checked to ensure that ALL devices plugged into the wall jacks serviced by your DSL phone number (except the DSL modem) have filters fitted.
All jacks have filters except DSL modem jack
7) Confirm that you’ve powered off the modem and started it again and whether or not that made any changes with your problem.
Power cycled modem multiple times with issues still present
8) Do you hear any type of noise on the DSL phone line or any other unusual telephone symptoms?
Phone line has no noticeable noise.
Line Stats:
Saturday 11/14/09
To Modem To Internet
Max allowed Speed (kbps) 6016 768
SN Margin (dB) 8 16.0
Line Attenuation (dB) 25 11.0
Loss of signal 0 204
Loss of frame 0 0
CRC Errors 2881 5
Line Stats:
Tuesday 11/17/09
To Modem To Internet
Max allowed Speed (kbps) 6016 768
SN Margin (dB) -4.0 19.0
Line Attenuation (dB) 25 11.0
Loss of signal 0 6837116
Loss of frame 0 0
CRC Errors 288850 139480 |
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tonydi
Premium,MVM
join:2001-05-11
San Jose, CA
| said by floppy1876  :CRC Errors 288850 139480 There's your problem! You get so many CRC errors that it knocks your sync down. You have to determine what's causing the errors, which may or may not be too difficult.
Does it happen at random times of the day and night, or do the sync losses occur during specific windows of time, like dusk till morning, that sort of thing?
Simple stuff....make sure the modem is away from other electrical devices like monitors, halogen desk lights, power bricks for things like printers, etc. Check that the phone cord going to the modem also gets routed away from those sources.
Then do a DMT graph and post the graph along with the table of numbers below it. Here's how....
»SBC DSL FAQ »How can I check for the maximum attainable sync speeds with a 5100b/4100 modem?
Ideally, doing one of these tests when things are ok and one when they degrade might help find sources of the interference if it's something that's off most of the time and then gets turned on.
Then you'd want to do the same DMT graph/table while connected to the test jack on your NID if you have one. Here's how...
»AT&T Southeast Forum FAQ »How to check modem stats, synch rates & speeds from test jack at the NID.
This eliminated your residences inside wiring as a possible source of the interference.
Good hunting! |
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floppy1876
join:2004-04-04
Stockton, CA
| reply to floppy1876
I've verified that the DSL modem is away from any other electrical device that could cause interferance.
Here is the DMT graph and the information for your review.
Downstream Current Rate (Reported): 6016
Downstream Maxrate (Reported): 7808
Downstream Bit Margin (Calculated): 432
Upstream Current Rate (Reported): 768
Upstream Maxrate (Reported): 1056
Bit tones with notches/missing bits:
bit(s) 37:41 159.5625 - 181.125 KHz
bit(s) 62:63 267.375 - 276 KHz
bit(s) 75:79 323.4375 - 345 KHz
bit(s) 104 448.5 - 452.8125 KHz
bit(s) 129 556.3125 - 560.625 KHz
bit(s) 131:137 564.9375 - 595.125 KHz
bit(s) 140:141 603.75 - 612.375 KHz
bit(s) 148:159 638.25 - 690 KHz
bit(s) 164 707.25 - 711.5625 KHz
bit(s) 168:181 724.5 - 784.875 KHz
bit(s) 183:191 789.1875 - 828 KHz
bit(s) 198:207 853.875 - 897 KHz
bit(s) 210 905.625 - 909.9375 KHz
bit(s) 216:217 931.5 - 940.125 KHz
bit(s) 225:233 970.3125 - 1009.125 KHz
bit(s) 253:255 1091.0625 - 1104 KHz
Since I live in a condo i'm unable to access the NID so I can't run any tests to rule out interior wiring. |
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tonydi
Premium,MVM
join:2001-05-11
San Jose, CA
1 edit | Ok, we've got a baseline so let's see if you can capture one when you're having connection issues. It may be tough if the conditions that knock you offline then go away until the next time but them's the breaks when you're trying to identify intermittent problems.
You mentioned Friday night/Sat morning, but didn't really address my question about the time window when this happens or if it's consistent...only at night, random throughout the day/night, etc.
Our resident DMT expert, d_l , looked at your graph and said that you have lots of little interferences based on all the little notches, but he thought there were probably too many to be caused by local AM radio stations. We're hoping that those notches will expand when the interference source comes back again, which may help determine a source.
Bummer about not being able to test at a NID, since that would eliminate your internal wiring and the apt's interior environment as being a source.
You might also want to try the ol' radio trick when the interference cranks up. Here's a FAQ....
»Ameritech - SBC FAQ »My DSL loses sync regularly. How can I detect interference with an AM Radio? |
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floppy1876
join:2004-04-04
Stockton, CA
| reply to floppy1876
Finally got an AT&T tech to come out and take a look at my DSL connection. He ran some line tests and discovered that the signal strength was low so he ended up finding another pair that had better signal strength. Hopefully this will resolve my DSL issues.
Thanks to all that helped me with my issue. |
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tonydi
Premium,MVM
join:2001-05-11
San Jose, CA | Keeping my fingers crossed for you. You should take another set of stats and DMT graph/table now that you're on a different pair so you have a baseline to see how much different things are. |
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floppy1876
join:2004-04-04
Stockton, CA
| reply to floppy1876
Here is an updated set of stats and DMT graph/table that should show what the different pair is giving me. Hopefully you guys can take a look and tell me whether or not this pair is a better improvement over the last.
Downstream Current Rate (Reported): 6016
Downstream Maxrate (Reported): 9440
Downstream Bit Margin (Calculated): 476
Upstream Current Rate (Reported): 768
Upstream Maxrate (Reported): 1056
Bit tones with notches/missing bits:
bit(s) 37:39 /159.5625/- 172.5 KHz
bit(s) 63 /271.6875/ - 276 KHz
bit(s) 69:70/297.5625/ - 306.1875 KHz
bit(s) 73:74 /314.8125/ - 323.4375 KHz
bit(s) 147:152 /633.9375 / - 659.8125 KHz
bit(s) 156:157 /672.75/ - 681.375 KHz
bit(s) 225:233 /970.3125/ - 1009.125 KHz
bit(s) 243:250 /1047.9375/ - 1082.4375 KHz
bit(s) 255 /1099.6875 /- 1104 KHz |
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d_l
Barsoom
Premium,MVM
join:2002-12-08
Reno, NV
| reply to floppy1876
Dramatic improvement! Hardly any notches! A huge boost in the maxrate!
I can't believe the elimination of the notches (interference) is simply due to improved DSL signal into your place that "drowns" out some local interference affecting your inside wiring. The amount of improvement shown by the pair switch looks more like the loop pair itself was picking up the interference and not your inside wiring. If that is the case, you couldn't have found a local noise source with the AM radio. |
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