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dicen

join:2007-05-16
90000

Comcast throttling high bandwidth users secretly.

Comcast has just started throttling my link at 200 KB/s down after a few minutes of >100 KB/s (lowest I tested) usage. This effects everything. So encrypting Bittorrent (I have) doesn't matter. Lowering its usage doesn't matter. Just browsing the web after this becomes a painful experience. I have the highest speed account level 8 Mbits/s (1 MB/s). Testing my link with the tools on this site will not show this. You have to actually use the bandwidth for a few minutes before the throttle is activated. (Like I need 8 Mbits/s for only a few minutes at a time.)

I am in Sunnyvale, CA (the Bay Area). I am now looking for a new ISP. Does anyone know of any Fiber ISPs available here? I just moved. I would love Verizon but it isn't here. Will it be?

What did I do to deserve this? I never used more then 500 KB/s peak. Usually around 400 KB/s on and off for a few days downloading some videos I paid for. Total around 30GB.

I encourage everyone on Comcast to look for this. It is very sneaky. You may be capped, you just don't know it.

dicen


dadkins
Can you do Blu?
Premium,MVM
join:2003-09-26
Hercules, CA
kudos:18

1 edit
Click for full size
How long?
I'm here in the Bay Area as well... they aren't throttling me!
--
Think outside the Fox... Opera

dicen

join:2007-05-16
90000
said by dadkins:

How long?
I'm here in the Bay Area as well... they aren't throttling me!
I just discovered it today. But, I think it started a few days ago. I just tested again and it looks like it kicks in at >150 KB/s for a few minutes. I am definitely gone. This is of course what they want. But, when everyone leaves for Verizon what will they have? Typical Corporate America thinking. Idiots. I suggest everyone start looking.

dicen


dadkins
Can you do Blu?
Premium,MVM
join:2003-09-26
Hercules, CA
kudos:18
As you can see by my pics... I am pulling 8.6mbps steady.
I think there might be some other problem aside from throttling.

Sorry that you are leaving. Good luck with whomever you choose as you new provider!
--
Think outside the Fox... Opera

dicen

join:2007-05-16
90000
said by dadkins:

As you can see by my pics... I am pulling 8.6mbps steady.
I think there might be some other problem aside from throttling.

Sorry that you are leaving. Good luck with whomever you choose as you new provider!
Well, I don't think they do this to everyone. This just happened to me after downloading a lot of data over a few days. It appears to be very smart throttling. They look at how much I am downloading, for how long, and I think they may even look at the number of network connections I have.

Like I said high bandwidth users. You get put in a penalty box.

dicen

dicen

join:2007-05-16
90000
You know, you sound like you work for Comcast. I wouldn't be surprised. This throttling is not a problem on my end. I go from >500 KB/s to exactly 200 KB/s at exactly the same amount of time, every time I test it. It is like clock work.

dicen


dadkins
Can you do Blu?
Premium,MVM
join:2003-09-26
Hercules, CA
kudos:18

2 recommendations

said by dicen:

You know, you sound like you work for Comcast. I wouldn't be surprised. This throttling is not a problem on my end. I go from >500 KB/s to exactly 200 KB/s at exactly the same amount of time, every time I test it. It is like clock work.

dicen
I'll take that as a compliment!
I don't work for Comcast.
I don't work for anyone actually - being disabled sucks!

I can still peg my connection, and I live just North of you here in The Bay Area.

Other than throttling, it could be your headend, some fried router between you and where ever, a modem or router problem at your end, or even your computer.

Since you are sure it is not within your house(I'll give you the benefit of the doubt), then any of the other items outside the house between you and ??? may be borked.

Comcast has never throttled my connection.
Ask anyone here in this Comcast forum what my connection is like.

If you would like, I will see if I can get someone that *DOES* work for Comcast to come to this thread and reply...

--
Think outside the Fox... Opera


CableTool
Poorly Representing MYSELF.
Premium
join:2004-11-12

1 recommendation

reply to dicen
I only have this to add.


RR Conductor
NWP RR Inc.,serving NW CA
Premium
join:2002-04-02
Redwood Valley, CA
kudos:1

1 edit

1 recommendation

reply to dadkins
No throttling up here in Mendocino County on Comcast either, we're part of the Comcast North Bay Network (Marin, Napa, Sonoma, Mendocino Counties).

lart

join:2002-08-19
united state

1 edit
reply to dicen
How are you testing your download speeds? most clients will take an average speed. I think you are giving comcast more credit then they deserve.


Jahntassa
What, I can have feathers
Premium
join:2006-04-14
Conway, SC
kudos:4

1 recommendation

reply to CableTool
said by CableTool:

I only have this to add.
I second that!


b1gdr3
I Blame Your Mother

join:2001-07-28
York, PA

1 recommendation

reply to dicen
said by dicen:

I encourage everyone on Comcast to look for this. It is very sneaky. You may be capped, you just don't know it.
I guess it's not possible that the server you are downloading from sucks.....no that's not possible, Comcast has to be doing it huh {/sarcasm}
--
I wasn't born with enough middle fingers.


comcasts network

@mcleodusa.net

10 recommendations

I hate to break it to you but comcast's HFC network isn't designed to deliberately throttle as you are suggesting. If comcast thinks you're doing too much or going too fast on their network they simply reassign your modems config file and force it to reboot taking it offline until you call them.

Speedtests are flaky at best and torrents are far from reliable for speed tests as the seeder/leecher ratio makes a huge difference as well as upload issues.

Rather than doing a blind assumption of deliberate throttling, why don't you post your modem info, signal levels, equipment(router/wireless), and screen shots of http downloads from servers near you geographically and maybe the good users of this forum can help you fix your issue.


CableTool
Poorly Representing MYSELF.
Premium
join:2004-11-12

1 recommendation

reply to dicen
said by dicen:

I encourage everyone on Comcast to look for this. It is very sneaky. You may be capped, you just don't know it.

dicen
Dude, Id know. There is nothing "Sneaky" about going down to 100-200KB/s. Everyone would notice. I suggest you take a hard look at your system and its settings. Im sure everything is perfect, untouched and optimal.. but stuff usually is until it craps out.
--
CableFAQ.org/Technicians Unplugged


funchords
Hello
Premium,MVM
join:2001-03-11
Yarmouth Port, MA
kudos:6

1 edit

3 recommendations

reply to dicen
said by dicen:

You know, you sound like you work for Comcast. I wouldn't be surprised. This throttling is not a problem on my end. I go from >500 KB/s to exactly 200 KB/s at exactly the same amount of time, every time I test it. It is like clock work.
dicen, meet Dadkins, one of the most knowledgeable and helpful people here. He won't steer you wrong.

One other possibility is the "Optimistic Unchoke" effect. When a new peer connects, the other peer is supposed to give him a 33% (1 in 3) chance in getting the next optimistic unchoke. That means, within 30-40 seconds of connecting, 1 in 3 peers should start downloading to you. That download should last for at least 30 seconds. After that, you are in that peer's regular rotation for another optimistic unchoke (unless that peer selects you as one of its better reciprocators).

None of the above necessarily applies to seeds -- especially that last sentence, since seeds do not care about reciprocation.

So after joining a swarm, if you connect up to your swarm rather quickly, and if that swarm is light on full seeds, it could be (and should be) normal to have a bit of a drop that peaks about 1:10 minutes from the time you connect, and begins to drop 30-40 seconds later.

Just another theory for you to test. Personally, this one doesn't happen to me, because I don't connect up to swarms very fast -- about one new connection every 3-4 seconds -- so the effect isn't very pronounced to me if it happens at all. (I'm really not a participant in any of the really popular torrent swarms -- my music/video tastes are just not hip enough.)
--
Robb Topolski -= funchords.com =- Hillsboro, Oregon USA
~ Keeper of the D-Link FAQ ~ Did you Search? ~ More features, Free! Join BBR! ~


toolkit

join:2001-01-16
Crystal Lake, IL
reply to dicen
I think funchords may have identified your problem. With Ethernet in general (not just BitTorrent, but all ethernet), every packet needs to be acknowledged. If you have an asymmetric connection (where download is a different rate than upload), you can easily create problems if you saturate the slower connection. In this case, if the upload connection gets saturated, you will see the download connection reduce performance to approximately equal the upload performance.

This has nothing to do with Comcast, or DOCSIS, or cable. It happens on DSL, and even asymmetric dial-up too - anything that has a different download and upload rate.

The problem is caused when the upload pipe is full. Then the ack packets for the download pipe can't be sent as fast as they want, and they have to wait in line with the other upload traffic. The end result is that both upload and download start operating at a speed near the slower of the two. The only time you wouldn't have to worry about this is if you had a link where the upload and download were the same rate (a symmetric link, like SDSL or a T1 line).

If BitTorrent is causing your upload pipe to saturate, I would look at limiting the upload. Most BitTorrent clients have the ability to limit the amount of upload bandwidth. I personally would limit it to about half of your total upload capability (yes HALF). If your advertised upload rate is 768Kbit/s, then I would limit the BT client to about 384Kbit/s or around 50 KBytes/s. That leaves plenty of room for other stuff to get into the stream, and you shouldn't notice any impact on web surfing.

Please try configuring your BT client to limit upload bandwidth. Failing that, try closing the client. Then see if your bandwidth almost immediately returns to normal. If it does, then you can be pretty sure this is the problem. Let us know what you find. We're here to help - really. Just remember to stay calm and you'll find a lot more help.

DMS1

join:2005-04-06
Plano, TX
said by toolkit:

With Ethernet in general (not just BitTorrent, but all ethernet), every packet needs to be acknowledged.
That's not true at all, but you are along the right lines. With TCP/IP over Ethernet, acknowledgements only come into play at the TCP level (which is OSI layer 4). IP (layer 3) and Ethernet (layer 2) are essentially send and pray protocols. However, because TCP requires acks, then anything above it, such as P2P applications (layer 6 or 7), is also dependent on acks.


DreamWraith
Premium
join:2004-04-07
Mount Vernon, WA
said by DMS1:

said by toolkit:

With Ethernet in general (not just BitTorrent, but all ethernet), every packet needs to be acknowledged.
That's not true at all, but you are along the right lines. With TCP/IP over Ethernet, acknowledgements only come into play at the TCP level (which is OSI layer 4). IP (layer 3) and Ethernet (layer 2) are essentially send and pray protocols. However, because TCP requires acks, then anything above it, such as P2P applications (layer 6 or 7), is also dependent on acks.
I hardly think the *technical* semantics change his point. Way to needlessly clarify something.

DMS1

join:2005-04-06
Plano, TX
said by DreamWraith:

said by DMS1:

said by toolkit:

With Ethernet in general (not just BitTorrent, but all ethernet), every packet needs to be acknowledged.
That's not true at all, but you are along the right lines. With TCP/IP over Ethernet, acknowledgements only come into play at the TCP level (which is OSI layer 4). IP (layer 3) and Ethernet (layer 2) are essentially send and pray protocols. However, because TCP requires acks, then anything above it, such as P2P applications (layer 6 or 7), is also dependent on acks.
I hardly think the *technical* semantics change his point. Way to needlessly clarify something.
No, it doesn't change his point, but your technically incorrect information could mislead others. For example, one might easily think that your argument extended to VOIP applications too, when in fact it doesn't because VOIP uses UDP instead of TCP.


toolkit

join:2001-01-16
Crystal Lake, IL

1 recommendation

You're right. I should have been more careful with my language. When I talk about ethernet, I often think of the entire TCP/IP stack. I should have used the term TCP, I guess, to make it more accurate.

In any case, I think there is a good chance a saturated uplink is the cause of the download problem the OP is seeing. Kudos to funchords for thinking of that.

sago5

join:2001-12-19
reply to dicen
It's instinct.

Sometimes, instinct is wrong in the details, but it's "approximately" correct in other ways.

Having a mistrust for Comcast has a basis in instict. Not necessarily specifically because of "throttling high bandwidth users secretly", obviously, but there is a question - what is broadband? What is a connection to the internet?

It just irritates me to no end when people side with the "powerful" and cop an attitude about it. Comcast is right because they have the power. I want to lick the soles of their shoes because that way I'll get brownie points that will allow me to feel good about myself. If I suck up to it, I'll "be like" the rich and powerful.

Couldn't be more wrong.

Get to the bottom of things - that's what we need to do. I agree.

Cop an attitude about selling your soul to the devil? Count me out of that one (I've learned my lesson on that one).

It ain't cool. Alert, awake, alive. Focused. Filled with empathy. Helping your fellow human beings. It's about reality, it's not about me, it's not about my situation, it's not about my opinions - it's about the task at hand - it's about the object or problem in question - on a larger scale, it's about building a better world - it's about helping each other out.

Being wrong is OK. Changing your mind is OK. Learning from your mistakes is OK, and good. Saying you're sorry is a first step. Life has a way of involving us - carrying us away with it.

I tend to be vocal, but in my heart, I care.

Instinct - there is an instinct about Comcast. That instinct is probably based on the fact that they have little competition. That instinct is based on the very same reasons that the US Govt created a bunch of Anti-Trust laws after the stock market crash that led to the Great Depression. That instinct is good. To have it knocked down in some abstract personal interest in brownie points only strengthens that instinct. It's a gut thing. It's a good thing.

But the important thing is to keep thinking about others, to help others, to help each other out. That's what it's all about, if you asked me.

And, weeding through the nonsense to get to the good stuff. Good days, bad days. That's life. Into each post some nonsense will accrete.

Whatever.

Peace, out.
Expand your moderator at work


wee96
Your Local Confederate

join:2000-04-12
Clinton Township, MI
reply to dicen

Re: Comcast throttling high bandwidth users secretly.

Theres load balancing going on in all areas, its not some big secret.


NormanS
I gave her time to steal my mind away
Premium,MVM
join:2001-02-14
San Jose, CA
kudos:12
Reviews:
·SONIC.NET
·Pacific Bell - SBC

4 edits

1 recommendation

reply to dicen
said by dicen:

Comcast has just started throttling my link at 200 KB/s down after a few minutes of >100 KB/s (lowest I tested) usage. This effects everything. So encrypting Bittorrent (I have) doesn't matter. Lowering its usage doesn't matter. Just browsing the web after this becomes a painful experience. I have the highest speed account level 8 Mbits/s (1 MB/s). Testing my link with the tools on this site will not show this. You have to actually use the bandwidth for a few minutes before the throttle is activated. (Like I need 8 Mbits/s for only a few minutes at a time.)
"Post hoc, ergo propter hoc" (in English, "After this, therefore because of this).

If BitTorrent downloads are your measure of speed, you are using the wrong measure. In the last two weeks I have downloaded 10G, or so, of anime. I had one torrent averaging 1kB/s down; so AT&T was throttling me? But another show, later, was pulled in at 254kB/s (I should max out at ~309kB/s). My results very, depending on peers; that 1kB/s download, for the longest time, only had two other peers, and we were all at 98.1% complete. Nobody had a complete copy; and when an uploader finally joined the torrent, he was a Comcast user splitting his meager upload bandwidth between three DSL downloaders, any one of whom had more than enough download bandwidth to saturate his upload bandwidth. Yeah, it was painfully slow.

Speed tests are best closest to your location. Trying to test your speed at a New Jersey Speakeasy site, with flash, from Sunnyvale, CA, isn't going to be the optimum test of your download. Try to find a site close to you, both geographically (nearer to Sunnyvale), and virtually (nearer to the Comcast network). Preferably one with a large file to download, so you will be at it for 5, or ten minutes. Probably hard to find one if your capacity is 8Mb/s down.
I am in Sunnyvale, CA (the Bay Area). I am now looking for a new ISP. Does anyone know of any Fiber ISPs available here? I just moved. I would love Verizon but it isn't here. Will it be?
Verizon is not an ILEC anywhere near Sunnyvale; they are only ILEC in former GTE territory. Sunnyvale is former Pacific Bell territory, making AT&T your ILEC. AT&T is only committing to U-Verse, which is not FTTH, but FTTN; nothing like FIOS. And, though they have 25Mb/s potential, they are reserving all but 6Mb/s for IPTV, so 6Mb/s would be the fastest you could get. But, AFAIK, AT&T is only deploying U-Verse in Cupertino. If you are fortunate enough to be within 5,000 feet of a CO, or 6,500 feet of an RT, you should be eligible for Elite DSL; 6016kbps/768kbps (but data throughput is only ~85% of those numbers), but you have an 80% probability of only qualifying for the Express (1536kbps/384kbps) service.
What did I do to deserve this? I never used more then 500 KB/s peak. Usually around 400 KB/s on and off for a few days downloading some videos I paid for. Total around 30GB.

I encourage everyone on Comcast to look for this. It is very sneaky. You may be capped, you just don't know it.
I urge you to do some more testing. I don't have a link to a local university site; I used one, once, in Santa Cruz. Dadkins may have a good, local source of a test download file.

Also, check your line stats. Wiring is not something which is permanently good; it can deteriorate. Splitters, as well.

I really don't have a lot of good cable test suggestions, though, being a DSL guy. But cable is much like DSL in this regard: You start troubleshooting locally, with common tools, and try to isolate the issue to either premises, or plant.


EDIT: Dadkins just pointed out a slight error: I posted "6kbps" where I should have posted "6Mbps"!
--
Norman
~Oh Lord, why have you come
~To Konnyu, with the Lion and the Drum


dadkins
Can you do Blu?
Premium,MVM
join:2003-09-26
Hercules, CA
kudos:18

2 edits
Santa Cruz - Nitro:

»nitro.ucsc.edu/

Stanford:

»netspeed.stanford.edu/

NOTE: These speed tests will likely show PowerBoost way in excess of your "normal" speeds.

For larger downloads, I use Flashget(free):
»www.flashget.com/en/download.htm

... and download one of the DL.TV videos:
»dl.tv/

That, and I am a member at a few Direct Download sites that can pretty much max my line*.

*As seen in my first post...

EDIT: Stanford is being kinda slow for me today - 7.09mbps

Santa Cruz is coming in at 12.61mbps(PowerBoost) on this wireless laptop.
--
Think outside the Fox... Opera

monkeysuit

join:2002-12-16
League City, TX
reply to dicen
Not trying to be rude, but I personally hope that Comcast DOES throttle high bandwidth users. It is you who borks the connection for the rest of us in your neighborhood, and I hope they continue to throttle (if that is what they are doing) to make you go elsewhere. Good riddance.


comcastuser

@comcast.net
said by monkeysuit:

Not trying to be rude, but I personally hope that Comcast DOES throttle high bandwidth users. It is you who borks the connection for the rest of us in your neighborhood, and I hope they continue to throttle (if that is what they are doing) to make you go elsewhere. Good riddance.
Not to rude either, but when your usage does not change, but Comcast’s determination of high usage does, and you become the “high bandwidth user”, what will you say then? Hopefully, you understand the point I am making here.


dadkins
Can you do Blu?
Premium,MVM
join:2003-09-26
Hercules, CA
kudos:18

1 recommendation

reply to monkeysuit
said by monkeysuit:

Not trying to be rude, but I personally hope that Comcast DOES throttle high bandwidth users. It is you who borks the connection for the rest of us in your neighborhood, and I hope they continue to throttle (if that is what they are doing) to make you go elsewhere. Good riddance.
No throttling, they will warn you and suggest you cut back.
Failure to cut back will likely result in termination.

Problem solved.
--
Think outside the Fox... Opera


MadMANN3
Premium
join:2005-08-19
kudos:2

3 recommendations

reply to dicen
C'mon everyone. We all know that the OPs setup from the computer to the plant is flawless. So this conspiracy-driven secret throttling claim just HAS to be true. Everyone leave for Verizon right now!



comcastuser

@comcast.net
reply to dadkins
said by dadkins:

Failure to cut back will likely result in termination.

Problem solved.
Cut back to what? I have yet to hear a figure for Comcast on every different over usage scenario what an acceptable usage is. Not to turn this into another invisible cap thread, but it is never a definitive “problem solved”.