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Sporkman
October 19th, 2007, 03:45 PM
http://www.msnbc.msn.com/id/21376597/



Comcast blocks some Internet traffic

Tests confirm data discrimination by number 2 U.S. service provider

By Peter Svensson
Updated: 9:36 a.m. ET Oct. 19, 2007

NEW YORK - Comcast Corp. actively interferes with attempts by some of its high-speed Internet subscribers to share files online, a move that runs counter to the tradition of treating all types of Net traffic equally.

The interference, which The Associated Press confirmed through nationwide tests, is the most drastic example yet of data discrimination by a U.S. Internet service provider. It involves company computers masquerading as those of its users.

If widely applied by other ISPs, the technology Comcast is using would be a crippling blow to the BitTorrent, eDonkey and Gnutella file-sharing networks. While these are mainly known as sources of copyright music, software and movies, BitTorrent in particular is emerging as a legitimate tool for quickly disseminating legal content.

The principle of equal treatment of traffic, called "Net Neutrality" by proponents, is not enshrined in law but supported by some regulations. Most of the debate around the issue has centered on tentative plans, now postponed, by large Internet carriers to offer preferential treatment of traffic from certain content providers for a fee.

Comcast's interference, on the other hand, appears to be an aggressive way of managing its network to keep file-sharing traffic from swallowing too much bandwidth and affecting the Internet speeds of other subscribers.

Number two provider

Comcast, the nation's largest cable TV operator and No. 2 Internet provider, would not specifically address the practice, but spokesman Charlie Douglas confirmed that it uses sophisticated methods to keep Net connections running smoothly.

"Comcast does not block access to any applications, including BitTorrent," he said.

Douglas would not specify what the company means by "access" _ Comcast subscribers can download BitTorrent files without hindrance. Only uploads of complete files are blocked or delayed by the company, as indicated by AP tests.

But with "peer-to-peer" technology, users exchange files with each other, and one person's upload is another's download. That means Comcast's blocking of certain uploads has repercussions in the global network of file sharers.

Comcast's technology kicks in, though not consistently, when one BitTorrent user attempts to share a complete file with another user.

Each PC gets a message invisible to the user that looks like it comes from the other computer, telling it to stop communicating. But neither message originated from the other computer — it comes from Comcast. If it were a telephone conversation, it would be like the operator breaking into the conversation, telling each talker in the voice of the other: "Sorry, I have to hang up. Good bye."

Matthew Elvey, a Comcast subscriber in the San Francisco area who has noticed BitTorrent uploads being stifled, acknowledged that the company has the right to manage its network, but disapproves of the method, saying it appears to be deceptive.

"There's the wrong way of going about that and the right way," said Elvey, who is a computer consultant.

All types of content

Comcast's interference affects all types of content, meaning that, for instance, an independent movie producer who wanted to distribute his work using BitTorrent and his Comcast connection could find that difficult or impossible — as would someone pirating music.

Internet service providers have long complained about the vast amounts of traffic generated by a small number of subscribers who are avid users of file-sharing programs. Peer-to-peer applications account for between 50 percent and 90 percent of overall Internet traffic, according to a survey this year by ipoque GmbH, a German vendor of traffic-management equipment.

"We have a responsibility to manage our network to ensure all our customers have the best broadband experience possible," Douglas said. "This means we use the latest technologies to manage our network to provide a quality experience for all Comcast subscribers."

The practice of managing the flow of Internet data is known as "traffic shaping," and is already widespread among Internet service providers. It usually involves slowing down some forms of traffic, like file-sharing, while giving others priority. Other ISPs have attempted to block some file-sharing application by so-called "port filtering," but that method is easily circumvented and now largely ineffective.

Comcast's approach to traffic shaping is different because of the drastic effect it has on one type of traffic — in some cases blocking it rather than slowing it down — and the method used, which is difficult to circumvent and involves the company falsifying network traffic.

The "Net Neutrality" debate erupted in 2005, when AT&T Inc. suggested it would like to charge some Web companies more for preferential treatment of their traffic. Consumer advocates and Web heavyweights like Google Inc. and Amazon Inc. cried foul, saying it's a bedrock principle of the Internet that all traffic be treated equally.

To get its acquisition of BellSouth Corp. approved by the Federal Communications Commission, AT&T agreed in late 2006 not to implement such plans or prioritize traffic based on its origin for two and a half years. However, it did not make any commitments not to prioritize traffic based on its type, which is what Comcast is doing.

The FCC's stance on traffic shaping is not clear. A 2005 policy statement says that "consumers are entitled to run applications and services of their choice," but that principle is "subject to reasonable network management." Spokeswoman Mary Diamond would not elaborate.

Opposition

Free Press, a Washington-based public interest group that advocates Net Neutrality, opposes the kind of filtering applied by Comcast.

"We don't believe that any Internet provider should be able to discriminate, block or impair their consumers ability to send or receive legal content over the Internet," said Free Press spokeswoman Jen Howard.

Paul "Tony" Watson, a network security engineer at Google Inc. who has previously studied ways hackers could disrupt Internet traffic in manner similar to the method Comcast is using, said the cable company was probably acting within its legal rights.

"It's their network and they can do what they want," said Watson. "My concern is the precedent. In the past, when people got an ISP connection, they were getting a connection to the Internet. The only determination was price and bandwidth. Now they're going to have to make much more complicated decisions such as price, bandwidth, and what services I can get over the Internet."

Several companies have sprung up that rely on peer-to-peer technology, including BitTorrent Inc., founded by the creator of the BitTorrent software (which exists in several versions freely distributed by different groups and companies).

Ashwin Navin, the company's president and co-founder, confirmed that it has noticed interference from Comcast, in addition to some Canadian Internet service providers.

"They're using sophisticated technology to degrade service, which probably costs them a lot of money. It would be better to see them use that money to improve service," Navin said, noting that BitTorrent and other peer-to-peer applications are a major reason consumers sign up for broadband.

BitTorrent Inc. announced Oct. 9 that it was teaming up with online video companies to use its technology to distribute legal content.

Affecting others

Other companies that rely on peer-to-peer technology, and could be affected if Comcast decides to expand the range of applications it filters, include Internet TV service Joost, eBay Inc.'s Skype video-conferencing program and movie download appliance Vudu. There is no sign that Comcast is hampering those services.

Comcast subscriber Robb Topolski, a former software quality engineer at Intel Corp., started noticing the interference when trying to upload with file-sharing programs Gnutella and eDonkey early this year.

In August, Topolski began to see reports on Internet forum DSLreports.com from other Comcast users with the same problem. He now believes that his home town of Hillsboro, Ore., was a test market for the technology that was later widely applied in other Comcast service areas.

Topolski agrees that Comcast has a right to manage its network and slow down traffic that affects other subscribers, but disapproves of their method.

"By Comcast not acknowledging that they do this at all, there's no way to report any problems with it," Topolski said.

CaptainTux
October 19th, 2007, 03:47 PM
I do nto have a link, but I have also heard speculation that comcast is reducing the priority of Vonage packets to make Comcast voice a more attractive alternative.

cogadh
October 19th, 2007, 03:51 PM
If you use an encrypted connection for BitTorrent, this is not a problem. I have Comcast and I download/upload all the time. In fact, I got the Gutsy torrent in under 20 minutes and continued uploading it at fully saturated upload speeds (384 kbps) for at least 3 hours after that (then I had to reboot and install Gutsy).

This is quite disturbing that Comcast would so something like this. One of the reasons I first got their service was due to their neutrality. Sad to see that is no more.


I do nto have a link, but I have also heard speculation that comcast is reducing the priority of Vonage packets to make Comcast voice a more attractive alternative.
If you find that link, please post it. I also happen to be a Vonage customer and Comcast better not screw with that. If Comcast charged a reasonable amount of money for their phone service, I might use it, but when it costs $40 and Vonage is only $20 for the same exact features, why would I bother with Comcast?

moshuptrail
October 20th, 2007, 02:11 AM
I have Comcast and I can't do anything that involves BitTorrent - including perfectly legitimate podcasts of radio shows. It goes for a few minutes and then Linux locks up solid. I have to cycle the power and reboot to get it running again. (reminds me of windows 3.1)

I'll look for encryption options, but some programs don't give you much control over how they use BitTorrent. I've had trouble with both Rythmbox and gpodder.

bruce89
October 20th, 2007, 02:15 AM
My ISP (Pipex) shapes Bittorrent even if it is encrypted.

Nekiruhs
October 20th, 2007, 03:24 AM
My ISP (Pipex) shapes Bittorrent even if it is encrypted.
Unfortunately, theres a difference between shaping and blocking. Shaping adjusts priority. Blocking outright denies access. My ISP blocks seeding torrents. (*cough* COMCAST *cough* ) But I bought the service before they did this, I am reevaluating my decision,

Billy_McBong
October 20th, 2007, 04:03 AM
if i had a choice i wouldn't use comcast.
but unfortunately i don't have a choice:(

stalker145
October 20th, 2007, 04:55 AM
ComCast: "Oh, dear, did we oversell our bandwidth again?"

FTA: I LOVED Navin's comment that they should use the money to build better infrastructure. Combine that with not overselling and they'll be OK. I mean, really, how hard is it to throttle total bandwidth to match your network's abilities?

A little math... Total bandwidth / total customers we can possibly have = bandwidth per customer. If the customer reaches that bandwidth, they don't hurt anyone.

bah

RoadRunner's pulling this trash also. I've noticed that i can usually get a pretty decent downspeed, but the up is somewhere between little and none. Do they admit it? Nope. Do I have a choice? Nope.

Incense
October 20th, 2007, 05:26 AM
I have to encrypt all my bit torrent traffic, and use openDNS just so the internet will act normal. I hate comcast as an ISP, but they are the fastest in my area,

Polygon
October 20th, 2007, 06:10 AM
this is really old, i posted a topic about this a while ago...and it sucks because now i cannot seed any torrents, which makes me feel like a moocher......maybe because i am :D

but yeah comcast provides excellent service (at least in my area)....its just that this little thing sucks =/

Overbyte
October 20th, 2007, 06:30 AM
I do nto have a link, but I have also heard speculation that comcast is reducing the priority of Vonage packets to make Comcast voice a more attractive alternative.

Maybe these will help:

Here (http://blogs.zdnet.com/ip-telephony/?p=961)
Here (http://blogs.zdnet.com/ip-telephony/?p=952)
And here (http://www.vonage-forum.com/ftopic11377.html)
Don't forget this one too (http://www.dslreports.com/shownews/AP-Discovers-Comcast-Traffic-Shaping-88591)

Hey my ISP (PLDT) is on the Broadband Reports spotlight! They do traffic shaping and blocking users who consume "too much" bandwidth (but they deny it of course), and they have a monopoly on the telecom business. Worst ISP in the world, if you can imagine :)

$40 a month for 1mbps downstream max, well in reality you get like 128 kbps max. And the customer support are as dumb as a rock. AND you pay like $150 if you decide to downgrade. :guitar:

cogadh
October 20th, 2007, 07:50 PM
I have Comcast and I can't do anything that involves BitTorrent - including perfectly legitimate podcasts of radio shows. It goes for a few minutes and then Linux locks up solid. I have to cycle the power and reboot to get it running again. (reminds me of windows 3.1)

I'll look for encryption options, but some programs don't give you much control over how they use BitTorrent. I've had trouble with both Rythmbox and gpodder.
In response to your PM, I don't know how to encrypt traffic on anything other than Azureus. It offers transport encryption as part of the advanced options in the client. I use RC4 encryption and don't allow fallback options for non-encrypted traffic. For whatever reason, that seems to be enough to defeat Comcast's "big brother" act as I am able to download and seed at nearly fully saturated bandwidth any time of the day. I do also use an IP blocker (PeerGuardian 2 in Windows, MoBlock in Linux) which may help some, though I'm not sure how.

Incense
October 20th, 2007, 10:48 PM
In response to your PM, I don't know how to encrypt traffic on anything other than Azureus. It offers transport encryption as part of the advanced options in the client. I use RC4 encryption and don't allow fallback options for non-encrypted traffic. For whatever reason, that seems to be enough to defeat Comcast's "big brother" act as I am able to download and seed at nearly fully saturated bandwidth any time of the day. I do also use an IP blocker (PeerGuardian 2 in Windows, MoBlock in Linux) which may help some, though I'm not sure how.

In ktorrent you just check a box to enable encryption, and there is an ip blocking plug in. Works fine for me under comcast. Uncheck the encryption box, and every torrent stalls. Nice.

moshuptrail
October 21st, 2007, 03:57 PM
According to the article, what Comcast does is to monitor traffic and identify traffic coming to/from Bittorrent clients. It then sends each client a "reset" message which kills the download.

If that is the case, then perhaps an IP blocker might work. But you would have to have one on each end of the Bittorent connection since both ends get the reset command.

Probably what encryption does is to make it difficult or impossible for Comcast to identify the traffic as Bittorrent. The article also said that Comcast is not doing this in all markets - so you may just be lucky.


Also, When I first got Vonage I was able to send faxes over the standard phone connection. Later though, this capability went away. I can't tell if it was just due to increased traffic, or Vonage trying to sell me a special fax line, or Comcast trying to mess up Vonage.

Let's face it, we need more competition in the high-speed ISP market.

Meanwhile, maybe the Bittorrent folks can work on making their traffic less easy to identify and the clients less easy to spoof.

misfitpierce
October 21st, 2007, 04:10 PM
Encrypt for torrenting legal or not and change ports often... Youll be alright.

moshuptrail
October 21st, 2007, 05:34 PM
Evidently that works for Azureus, but not for other programs, like Rythmbox, or gpodder.

Does Azureus handle podcasts? (that's mostly what I'm downloading)

moshuptrail
October 21st, 2007, 05:47 PM
Suggestion from a non-programmer:
Could BitTorrent be written as a stand-alone service that could be called by many programs? (Or is it already?) That way it could be highly configurable with focus put on performance, etc.



gpodder Rythmbox Azureus other
^ ^ ^ ^
| | | |
+----------------+--------+--------+--------------+
|
|
BitTorrent Service Layer
|
|
Internet

Polygon
October 21st, 2007, 08:34 PM
Encrypt for torrenting legal or not and change ports often... Youll be alright.


even if you encrypt your torrent traffic it still gets reset by comcast

cogadh
October 21st, 2007, 08:36 PM
According to the article, what Comcast does is to monitor traffic and identify traffic coming to/from Bittorrent clients. It then sends each client a "reset" message which kills the download.

If that is the case, then perhaps an IP blocker might work. But you would have to have one on each end of the Bittorent connection since both ends get the reset command.
You're assuming that both ends of the connection are on Comcast. If one client is on some other service and is connecting to my client on Comcast, there is no way Comcast could or would send the other client a reset message.


Probably what encryption does is to make it difficult or impossible for Comcast to identify the traffic as Bittorrent. The article also said that Comcast is not doing this in all markets - so you may just be lucky.
That's exactly what encryption does. By the same token, that's why you should use a non-standard port for BitTorrent UDP/TCP connections, since it is reasonable to assume that they are already monitoring the common ports. I can confirm that Comcast is definitely pulling this junk in my market, as disabling encryption or using a default port definitely kills uploads for me.

even if you encrypt your torrent traffic it still gets reset by comcast
I'm afraid that is just not true. If you have encryption configured correctly, you will not get your uploads killed. I can show this on my system easily, as I explained above.

moshuptrail
October 21st, 2007, 10:48 PM
You're assuming that both ends of the connection are on Comcast. If one client is on some other service and is connecting to my client on Comcast, there is no way Comcast could or would send the other client a reset message.

Why not? We've already established an unethical pattern of behavior. All they need to know is the IP address and port, and bing! you are dead.

happysmileman
October 22nd, 2007, 12:03 AM
Suggestion from a non-programmer:
Could BitTorrent be written as a stand-alone service that could be called by many programs? (Or is it already?) That way it could be highly configurable with focus put on performance, etc.



gpodder Rythmbox Azureus other
^ ^ ^ ^
| | | |
+----------------+--------+--------+--------------+
|
|
BitTorrent Service Layer
|
|
Internet



Seems like it could be used as a library, and looking at some KDE libraries like KHTML and the embedded text editor it'd appear very appealing and efficient (not trying to start a flame war, I'm sure GNOME has one or two libraries as well, but KDE's are a much better example here)

It actually sounds like it could be a good idea at first glance, but that all depends, most computer have 1 bit-torrent client at most and it's not necessarilly worth it to have a library just for it. It could be useful for developers but then it depends who's going to use it?

Polygon
October 22nd, 2007, 12:32 AM
if you read the articles about this, it says that encryption DOES NOT STOP IT. If you really want me to go find quotes i will but im lazy atm. Ive tried encryption with 3 different clients on both windows and linux and every time i try to seed a torrent all the peers eventually disconnect from me and i get no upload

and what comcast does with this program is that they dont send a reset message to the the other person..

what they do is...lets say for example person a is using comcast and is seeding to person B. person a starts seeding..but then comcast's little program says 'uh nh' and sends a reset message to person a which LOOKS like it came from person b saying 'reset the connection'...and then the two are disconnected.

BUT...ive read that if the two people are both on comcast...then they can seed to each other.

cogadh
October 22nd, 2007, 02:01 AM
The articles are wrong. I do this everyday on Windows and Linux with Azureus, if you configure encryption correctly, i.e. RC4 with no fallback options for non-encrypted connections, Comcast does not stop the traffic. I've had the Gutsy torrent running for two days staying consistently at 280 - 320 kbps (max up speed of 384 kbps, but I limit it to 320 kbps). If I turn off encryption, the uploads die in less than 5 minutes. Turn encryption back on and the upload stays solid.

moshuptrail
October 22nd, 2007, 02:10 AM
Well, we all know how accurate reporters are.

I just found out how to change the ports used by gnome-bittorent, which seems to be used my some of the gnome programs, and it helps Rythmbox a little. At least I was able to d/l a few podcasts.

I didn't try to d/l a lot though.

tempest
October 22nd, 2007, 02:16 AM
This must explain why I could not download any of the gutsy cd isos with BT, but direct download from the ubuntu site took a half hour. I let my BT client run for over 24 hours before I gave up and tried the direct download. I have never had that much trouble before with ubuntu BT downloads.

stalker145
November 2nd, 2007, 02:32 PM
WOOT!! (http://politics.slashdot.org/article.pl?sid=07/11/01/1910235) (Slashdot - FCC Complaint Filed Over Comcast P2P Blocking)

Hopefully this is good news for COMCAST users... and the rest of us, of course.

Polygon
November 2nd, 2007, 09:50 PM
lol...i would of just settled for having the 'delaying' of traffic lifted....but 195,000 dollars also sounds nice xD

FranMichaels
November 3rd, 2007, 01:20 AM
The articles are wrong. I do this everyday on Windows and Linux with Azureus, if you configure encryption correctly, i.e. RC4 with no fallback options for non-encrypted connections, Comcast does not stop the traffic. I've had the Gutsy torrent running for two days staying consistently at 280 - 320 kbps (max up speed of 384 kbps, but I limit it to 320 kbps). If I turn off encryption, the uploads die in less than 5 minutes. Turn encryption back on and the upload stays solid.

QFT

http://www.freedom-to-tinker.com/?p=1217

I use bittornado, and there is a suggested package in the Ubuntu repositories, which will allow it full encryption. I actually don't have to use it, but it allowed my sister to download the Gutsy iso with BT.

Billy_McBong
November 3rd, 2007, 01:40 AM
so this means i will be able to seed torrents again? yay :grin: