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js339

join:2007-03-10
Vancouver, WA

[CenturyTel] Extreme oversubscription, transparent proxying, & C

So where I live, there are only two T-1 lines to serve hundreds of customers. I'm guessing one of those T-1 lines (or its equivalent) is reserved for a medium security prison several miles up the road, which leaves a single T-1 line to serve all the residential customers on a DSLAM.

Hundreds of customers were upgraded from 1.5 to 7 to 10 Mbps, but they are still oversubscribed on the very same T-1. Apparently the DSLAM is part of a CDN / transparent proxy network, which is why they think they can get away with this level of oversubscription. I believe this to be the case, since occasional error messages indicate beyond doubt the presence of a transparent proxy server claiming to run "nginx" at a latency no more than that of the DSL line itself, which is about 30ms or so, not enough time, in any case, to reach actual content beyond the DSLAM on the internet if it has not been cached at the DSLAM itself.

When I visit one of those broadband speed test sites, the test download is apparently served straight from the DSLAM, because it is simply impossible to actually download 10Mbps through 1 or even 2 T-1 lines.

When I have to visit a secure site, and download actual content that is supposed to be secure and confidential, I find that my download speed has been absolutely limited to 250Kbps. This on a 10Mbps connection, compared with a 1.5Mbps connection in the distant past which was usable at full speed if there happened to be no congestion on the T-1 line at the time.

I think I have a problem with CTL selling a "10Mbps" internet connection which under no circumstances is capable of downloading more than 250Kbps of content that does not happen to be cached locally at the DSLAM.

So how can I make a complaint about this, and get it fixed?


joebleed

join:2002-05-28
Tarboro, NC

Re: [CenturyTel] Extreme oversubscription, transparent proxying,

where did you get the information that your area is being served by a single t1 line? How about the proxy?

Also, try torrents or just a large download of either a Microsoft service pack or linix or BSD iso.

i've been noticing my speed tests from speedtest.net have been reading slower than what i download at from torrents or direct from microsoft.

Random streaming vidoe would also be another test, though not as good.

GetMoney

join:2010-06-11
Reviews:
·Time Warner Cable
reply to js339
Ah, another conspiracy thread. My question is how do you know only one T1 serves hundreds of people. The service would be unusable if only 5% of these hundreds were online. I hate to say it but I'm pretty sure you're wrong. CTL likes to oversell, but this if this were true it would be downright criminal. Plus standard IMA dslam deployments they do typically have 8 T1's and usually that's for less than 100 people


clevere1
Premium
join:2002-01-06
Vancouver, WA
kudos:1
reply to js339
When I changed DNS servers to opendns .. my speeds were greatly improved.
--
Where's th' DAFFY DUCK EXHIBIT??

js339

join:2007-03-10
Vancouver, WA
reply to GetMoney
said by GetMoney :
The service would be unusable if only 5% of these hundreds were online.
Exactly. It's totally unusable if any of the neighbors happen to be online at the time, which is quite a bit of the time, in fact.
said by joebleed :
where did you get the information that your area is being served by a single t1 line?
By the same tech guy who had the nerve to try to sell me a T-1 line. Way out in the boondocks here, city slickers.
said by joebleed :
How about the proxy?
From time to time I get an error message that pops up almost immediately---30ms when I look at a tcpdump---that "nginx" failed to proxy some site or another. It certainly couldn't have come from further away than the DSLAM.
said by clevere1 :
When I changed DNS servers to opendns .. my speeds were greatly improved.
I have to try several times to even get a DNS response, no matter where I try to get it from, and then when I do, the connection to the site itself is still unbearably slow. And even when there is no congestion, I never get more than 250Kbps from a site that is not part of a CDN.

brad152

join:2006-07-27
Phoenix, AZ
Reviews:
·CenturyLink
reply to js339
i doubt they're putting a proxy at the DSLAM. My ping is never over 30-50ms when connecting to Skype with friends back in Ohio, and the way speedtest.net operates it's impossible for them to "cache" that since it generates random data for each and every speedtest performed.

this is to a server about 30mi from my house (i know exactly where the server is located)..



this is a 20/896k connection, and what i get all day.


joebleed

join:2002-05-28
Tarboro, NC
reply to js339
what does the error message say exactly?

Can you try the download test i suggested?

What router and modem are you using?

»nginx.org/en/
This reads almost as if it would be setup on the server side. I'm not really sure though. As if it were more to help load balancing on the server end.

js339

join:2007-03-10
Vancouver, WA
I don't do it that often, but it takes the better part of an hour to download a 650Mb ISO of any sort, and when I'm done, the transfer rate is never more than 250Kbps. And that's only when there's no congestion on the network. 1/40 their advertised speed. Not exaggerating.

nonymous
Premium
join:2003-09-08
Glendale, AZ
reply to js339
" Hundreds of customers were upgraded from 1.5 to 7 to 10 Mbps, but they are still oversubscribed on the very same T-1. "

You are getting 7 to 10 on a T1. Even with one customer that is not possible.

js339

join:2007-03-10
Vancouver, WA
said by nonymous :

You are getting 7 to 10 on a T1. Even with one customer that is not possible.

No I'm not getting 7 to 10. That's what they say I'm getting. Maybe 5-6 customers downloading actual content at 250Kbps. That's the capacity of the entire neighborhood. That's what they call 10Mbps.

nonymous
Premium
join:2003-09-08
Glendale, AZ
said by js339:

said by nonymous :

You are getting 7 to 10 on a T1. Even with one customer that is not possible.

No I'm not getting 7 to 10. That's what they say I'm getting. Maybe 5-6 customers downloading actual content at 250Kbps. That's the capacity of the entire neighborhood. That's what they call 10Mbps.

Only one T1 not possible learn some. Multiple t1 bonded maybe.


mooch
No Booing Allowed

join:2001-11-11
Dublin, OH
Reviews:
·Embarq Now Centu..
reply to js339
js339, if your Centurylink DSL performance is below what it should be, you can better demonstrate that by showing what speeds and pings your actually getting. Making assumptions on network specifications won't get you too far, especially when indicating a single T1 is serving hundreds of people who have a 10Mb connection.

Even if you're speeds are pathetic that doesn't mean your T1 theory is correct, even folks who have service off a fiber fed DSLAM can have poor speeds, especially in the evenings.

CenturyLink
VIP
join:2009-03-09
Boise, ID
kudos:7
reply to js339
Hello js339,

My name is Joey and I'm with CenturyLink. Our team would like to assist you with the issues you're having. We can find out what exactly is going on in your area and what's being done to resolve things. Please send us your account information, speed tests and any other helpful details to TalkToUs@CenturyLink.com. Thank you.

Joey H
@CenturyLinkHelp Team

zevus

join:2010-11-29
Chandler, TX
Reviews:
·CenturyLink
reply to js339
i could believe the prison being serviced by a T1

but a whole neighborhood?

a T1 is 1.544Mbps, or 1.536 useable by customer(s)

wasn't australia connected to the outside world with a single T1 in the late 80's? or was that an ISDN?