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routerdown's profile

Tutor

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8 Messages

Monday, October 3rd, 2016 4:14 AM

AT&T throttling bandwidth anytime a direct dropbox.com download is started

I have a Pace 5268AC router connected via the 18Mbps plan.

 

I spent about an hour tonight troubleshooting an issue with AT&T technician David who works via phone from Wisconsin. Here's what we finally deduced: Attempting to download a large (2GB) file via a web browser from dropbox.com results in my broadband WAN internet connection being throttled down to less than 1Mbps (with an effective download rate of <200Kbps.) A few minutes after the download is cancelled, the broadband WAN speed goes back up to normal.

 

How did we deduce this? David created a new network SSID on my router and had me only connect one device to it (so that no other devices would interfere with the test). The speeds were fine, in-line with the plan I have. I could visit sites, watch videos, run speedtest.net, etc. with no issues. Then, I would attempt to download a large file from dropbox.com. Within a minute of initiating the download, my overall broadband WAN connection speed would throttle down to <1Mbps. The download would suddenly become impossible (appearing to require 10+ hours to complete). If I tried to visit other sites, the connection was terrible. At one point, my broadband connection actually went down (the broadband light on the modem went red and I got an error showing "Broadband connection not available"). But then, if I stop the browser-based dropbox.com download, within minutes my broadband WAN connection speed goes right back up to ~18Mbps.

 

We tested this multiple times, and it is 100% reproducible. The AT&T network is simply rigged so that users cannot download large dropbox.com files directly.

 

You might say, "Well, the dropbox app and other filesharing apps use up a lot of bandwidth." But I wasn't using the dropbox app. I was using a web browser to download a single file. No filesharing apps are even installed on the one machine that was connected to the network.

 

You might say, "Well, the problem was that your download was eating up all the bandwidth, so the rest of your connection was slower." But that's not true. The download speed of the file itself went down to <200Kbps. And along with that, speed tests (both AT&T and Speedtest.net) showed speeds of <1Mbps. It wasn't that I was getting some great download speed on the file, and somehow the remaining bandwidth was "eaten up." Literally, my entire connection went down to <1Mbps.

 

This needs to be fixed. These are legal files I was downloading for legitimate purposes. AT&T should not be in the business of throttling my connection.

 

Screenshots below:1.png2.png3.png

3 Attachments

Tutor

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5 Messages

7 years ago

So, dropbox believes the issue lies with the ISP and i am inclined to agree since I can plug in my cable modem which still has service and my download/upload speed to dropbox immediately returns on all devices.

 

I thought i had found a work around using the dropbox app on my desktop since after I installed it, i was able to upload and download at about 100MBPS.  But I attempted to sync some folders and download some photos sent by a client today and speeds are back to about 1MBPS (which is insane) using the desktop app or direct download. Speed test still has me pegged at 900MB / Up and Down. Since I am getting adequate download speeds through google drive and other sites via a browser connection, the only thing i can figure is there is some sort of disconnect between the AT&T servers and dropbox that is not being fixedor something in the router/modem is blocking full access.

 

I am plugging my cable modem back in and using that so i can get a decent connection to drop box and get some work done. If AT&T can't get this fixed by the end of the week, i'll be cancelling my service...

Tutor

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5 Messages

7 years ago

It also seems time related ... I get 5+ Mbps using browser download from Dropbox website on my ATT Gigapower (i'm in Raleigh/Durham area) BEFORE 8:00AM Eastern...but after that I get <200 Kbps.

A few questions:

1)  Why can I get 30+ Mbps from Google Drive for the same file download on the same ATT Gigapower network but only 150 Kbps from Dropbox if it's an ATT issue?

2)  I've kept my TimeWarner (Spectrum) 200Mbps connection active which I still get 5Mbps (although it tends to throttle down to 2Mbps over the duration of the download)...so I switch over to that exclusively to do my web downloads from Dropbox...that points to ATT as culprit?

 

Ultimately, I think ATT and Dropbox need to get together.

 

I'm probably going the other way...dropping Dropbox and moving to Google Drive which regardless of ISP seems to have much faster download speeds in general.  I want to keep my access to Fiber at 1000Mbps...much better long-term strategic move I believe.

Tutor

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5 Messages

7 years ago

Totally, I do alot of video editing and big file transfers. If i could control what online drive my clients used to send me files, i would just switch to google drive. But, i never know when someone will send me 5 GB of video files to edit and that would literally take days over the AT&T fiber network, whereas it might take a few hours on the cable modem. Oh well...maybe it will get fixed in the future and i can consider switching. Shame though, because they messed up the grass in my front yard to get the line laid at the end of this Summer putting the fiber in...

Tutor

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5 Messages

7 years ago

One last interesting thing...if i go through a free proxy server, I can download at 10-12mbps on the same AT&T fiber line. If i use the same download link without the proxy, it goes down to less than 500kbps

here they are downloading at the same time:

 

 

proxytest.JPG

 

Tutor

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5 Messages

7 years ago

Today I tried "ipconfig /flushdns" and it seemed to help. Download speed improved from 350Kbps to 6.3Mbps. I'll see if this holds up and post results in a few days.

Tutor

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5 Messages

7 years ago

Today I tried "ipconfig /flushdns" and it seemed to help. Download speed improved from 350Kbps to 6.3Mbps. I'll see if this holds up and post results in a few days.

Contributor

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1 Message

7 years ago

@pancake011 - Thanks for sharing your results, I just got Gigabit Power ATT Service in NC (Raleigh  Area) and I am experiencing the exact same thing!  An ISO download from MSDN or  NVIDIA driver  download would slow down to horrible speeds <10MBps.  If I use VPN, I would get ~50MBps (max for that VPN connection) for the very same downloads!  This is clearly bandwidth throttling.   I was looking forward to a Gigabit connection for a long time but it has been a disappointment thus far.   Never had this issue with TW in my area.

Oh...interestingly enough, if I run speed test I do get awesome speeds -  900+ MBps Upload and Download!

Tutor

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5 Messages

7 years ago

voen17 - I gave up on ATT Gigapower...I had kept my TimeWarner service as a backup just in case and it turns out I needed it...I am now running my TWC 200Mbps service as primary ISP and will periodically check my ATT Gigapower service to see if it improves...my TV (fantastic quality) and phone are with ATT along with the Gigapower...all bundled for a great price...so I've kept everything (too much of a pain to go back anyway)...I'm just connecting to my TWC for internet.

 

Hopefully someone will post if there is any improvement with ATT.

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