DSL Modem Throughput Issue
dsluser804
Enthusiast - Level 2

Why would a DSL modem (Westell 327W) start lowering throughput to the one computer connected to it?

My connection speed from modem to computer started fluctuating about a week ago and now will only go up to 500 "K" bps.  The modem says it is connected to the DSL service line at 3 "M" bps.  Same for both wired and wireless connection.

I can connect to my neighbor's Verizon DSL wireless modem at full speed, no problem, but no longer to mine.  I've had Verizon DSL & modem for a couple years with only intermittent problems.

After several Verizon techs and several hours, I finally convinced them to send me a new one.  Nothing they did could prove it was my computer, and connecting to my neighbor sealed the case, thank goodness.

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1 Solution

Correct answers
Re: DSL Modem Throughput Issue
dsluser804
Enthusiast - Level 2

My connection has been constantly at speed and has had no drop or interruptions since it came back yesterday.  Therefore, I'm going to consider this resolved (just wish I knew for sure how).

Appreciate the info regarding the transceiver stats.  Perhaps if one checks those first, it might indicate line problems even when the modem shows DSL connect at speed and DSL tech support remote connection shows the line and everything is fine.  I haven't taken the modem outside, but will this weekend to see if the inside wiring is adding to the problem.

Lesson learned:  Contact local telco to check line equipment before spending hours with DSL tech support.

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Re: DSL Modem Throughput Issue
dslr595148
Community Leader
Community Leader

#1 Since you use a wireless router:

What level of Wireless Security is the router set to (For example WEP/WPA)?

#2 Do you have at least two computers behind this modem or only one?

#3 In the router go to Advanced -> UPnP.

#4 Is UPnP On or Off?

#5 Do you get slower speeds at certain times?

#6 Is the router configured to allow users from the net to connect, to one of your computers behind the router?

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Re: DSL Modem Throughput Issue
dsluser804
Enthusiast - Level 2

     Here's the info you asked about:

1) Set as it came for WEP 64 bit.

2) I have multiple computers but disconnected all but one when I started having problem to try to isolate. All data posted is with just one computer connected. However, I did try each computer one at a time and found they all had some problem, so I know it wasn't because of a computer.

3/4) Under Advanced, "UPnP Enable" is 'not' checked.

5) At first the drop seemed to be random and didn't last that long. I only use evenings and weekends. At first it just seemed to be slow page load. Eventually, I ran a speed test and found it had dropped but would run that agian in 10-15 minutes, and it would be back up, sometimes for quite a while and sometimes drop again shortly. Sunday afternoon though, it quit going back up and now just stays between 500 and 300 Kbps download, but upload is still around 700 constantly.

6) The router is using default settings.

     Just to reiterate, I can connect to my neighbor's Verizon DSL wireless at full speed download constantly. So it seems it's the modem, or download is being throttled by the local DSL equipment even though it connects to the modem at 3MB.

     I'm waiting to hear back on my request to check the local DSL that drives my phone line. I'm assuming that it's in Verizon's hands one way or another. My local phone service is also Verizon, so they own it all.

     Appreciate any help.

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Re: DSL Modem Throughput Issue
dslr595148
Community Leader
Community Leader

#1 For testing reasons, disable the wireless and test with a wired connection.

Does that improve the speed of any of the computers?

If so, this might tell us that it is a wireless (location, range, path, security) issue.

#2 In your router, post the modem stats from the modem combo.

The modem stats maybe at System Monitoring -> Advanced Status -> Transciever Stats

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Re: DSL Modem Throughput Issue
dsluser804
Enthusiast - Level 2

Mysteriously, today when I got home and checked, the speed had jumped way back up to 2.9MB down and 735K up.

I have not gotten a response on my request to check the local DSL equipment, but I'm assuming they did and found a problem at the neighborhood telco building. 

A year ago I had a static problem on my land line and slightly slower DSL speed, and the local telco (Verizon) made some changes to the local equipment to fix that which also corrected the DSL speed.  The Verizon Internet DSL support said there was nothing wrong then either.  I guess you have to really talk to telephone people to get anything fixed that isn't in the scripts!

Here's the additional info requested, although the answer to #2 is now showing full speed and not the state it was in the last few days.


1)  I have tested both wired and wireless with no difference.  As stated, I have used multiple computers.

2)  Transceiver Revision:      7.2.3.0       
Vendor ID Code:     4      
Line Mode:     G.DMT Mode      
Data Path:     Interleaved      
 
Transceiver Information     Downstream Path     Upstream Path
DSL Speed (Kbits/Sec)                  3360                      864
Margin (dB)                                       13.0                      10.0
Line Attenuation (dB)                         40.5                     26.0
Transmit Power (dBm)                      6.9                       11.9

I will monitor this for a few days before I claim it is resolved.  Would sure like to know what was changed to correct this since nothing has been done on this end.  It might help others in the future.

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Re: DSL Modem Throughput Issue
dslr595148
Community Leader
Community Leader

Here is what most of all that stuff means..

Margin (dB) - Signal to noise margin. 6 is pretty bad possibly unusable at times, 20 is very good. You normally want 12dB or better IIRC from back in my DSL days. The higher the number, the better to a point.

Line Attenuation - Measure the amount the signal has degraded. Below 20dB is excellent, above 50 is poor, fill in the dots for anything in between.

Transmit Power - The higher the number, the more power is required to transmit. This number will vary based on the other numbers.

--

Connect your modem directly to the NID, to see if the signal is better.

Points to

http://www.dslreports.com/faq/1317

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Re: DSL Modem Throughput Issue
dsluser804
Enthusiast - Level 2

My connection has been constantly at speed and has had no drop or interruptions since it came back yesterday.  Therefore, I'm going to consider this resolved (just wish I knew for sure how).

Appreciate the info regarding the transceiver stats.  Perhaps if one checks those first, it might indicate line problems even when the modem shows DSL connect at speed and DSL tech support remote connection shows the line and everything is fine.  I haven't taken the modem outside, but will this weekend to see if the inside wiring is adding to the problem.

Lesson learned:  Contact local telco to check line equipment before spending hours with DSL tech support.

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Re: DSL Modem Throughput Issue
dslr595148
Community Leader
Community Leader

@dsluser804 wrote:

 Lesson learned:  Contact local telco to check line equipment before spending hours with DSL tech support.


Interesting..

What number did you use?

Since they might not like that info public, please PM me.

And or, how did you find the number that you called?

Thanks.

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Re: DSL Modem Throughput Issue
dsluser804
Enthusiast - Level 2

At the top of the Verizon page click:

Support,  Contact us, then select Email on the page that comes up.

On the form select Internet service, for category use Support,

then sub-category select Report a repair or installation issue

Fill out your info on the rest of the form and type in a note to check local equipment because your DSL is having problems.

Other way is to just call the repair number for your normal phone line service which is what I did a whle back when my phone line was full of static and the DSL dropped.  They understood  and sounded local.

Re: DSL Modem Throughput Issue
Hubrisnxs
Legend

  Do yourself a favor and get rid of the interleave, and ask verizon to change it fast channel.     you should notice an immediate increase in performance.  


@dsluser804 wrote:

Mysteriously, today when I got home and checked, the speed had jumped way back up to 2.9MB down and 735K up.

I have not gotten a response on my request to check the local DSL equipment, but I'm assuming they did and found a problem at the neighborhood telco building. 

A year ago I had a static problem on my land line and slightly slower DSL speed, and the local telco (Verizon) made some changes to the local equipment to fix that which also corrected the DSL speed.  The Verizon Internet DSL support said there was nothing wrong then either.  I guess you have to really talk to telephone people to get anything fixed that isn't in the scripts!

Here's the additional info requested, although the answer to #2 is now showing full speed and not the state it was in the last few days.


1)  I have tested both wired and wireless with no difference.  As stated, I have used multiple computers.

2)  Transceiver Revision:      7.2.3.0       
Vendor ID Code:     4      
Line Mode:     G.DMT Mode      
Data Path:     Interleaved      
 
Transceiver Information     Downstream Path     Upstream Path
DSL Speed (Kbits/Sec)                  3360                      864
Margin (dB)                                       13.0                      10.0
Line Attenuation (dB)                         40.5                     26.0
Transmit Power (dBm)                      6.9                       11.9

I will monitor this for a few days before I claim it is resolved.  Would sure like to know what was changed to correct this since nothing has been done on this end.  It might help others in the future.


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