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Comcast Confirmed as Discriminating Against FileSharing Traffic
An anonymous reader writes "Comcast has been singled out as discriminating against filesharing traffic in quantitative tests conducted by the Associated Press. MSNBC's coverage of the discovery is quite even-handed. The site notes that while illegal content trading is a common use of the technology, Bittorrent is emerging as an effective medium for transferring 'weighty' legal content as well. '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.'" This is confirmation of anecdotal evidence presented by Comcast users back in August.
...noticing problems downloading the patches on Comcast?
Just wondering since WoW uses Bittorrent to distribute its patches (one example of a very legitimate use).
It is by my will alone my thoughts acquire motion; it is by the juice of the coffee bean that the thoughts acquire speed
I've posted this before, but it's pertinent and bears repeating, it's not just P2P traffic that Comcast is filtering. A sysadmin I know has been blogging on Comcast filtering corporate e-mail traffic as well.
http://kkanarski.blogspot.com/2007/09/comcast-filtering-lotus-notes-update.html
Set your bittorrent client to only use encrypted traffic. It fixes comcast's little red wagon fast.
Almost all up to date bittorrent clients support this.
Do not look at laser with remaining good eye.
Actually, this will hurt net neutrality because everyone is getting QoS confused with Net Neutrality!
QoS is legal, and it should exist. Prioritizing classes of traffic is OK, provided the classes are generic classes of traffic (e.g., email, web, ftp, p2p, voip, etc).
Net Neutrality is compatible with QoS. What Net Neutrality proponents want isn't avoidance of QoS, but to prevent deals where if you use Windows Live Search, it comes up instantly, while if you use Google, you'll find yourself waiting a good minute for the frontpage to load up. I.e., both use the same class of traffic (web), but service is differentiated based on who can pay.
So Comcast causing Bittorrent problems is OK for Net Neutrality. But if Comcast suddenly lets Blizzard's WoW updates unimpeded while causing problems for say, Linux ISO torrents, then that conflicts with Net Neutrality.
Basically, like traffic should be treated alike. But unlike traffic may be treated differently. So if Comcast charged an extra $10 for enhanced VoIP QoS, that's OK, as long as it's for all VoIP, not just say, Vonage only, or Skype.
Net Neutrality opponents like to bleat the Anti-QoS line because it's the easiest way to spread FUD, when they really mean "Google, pay us, or we'll make your page take ages to load, while making Windows Live Search load instantly".
Source quench is an ICMP message, similar to destination unreachable but less severe. It's a way for a host to tell another host (or router) that it's sending data too fast for it to process and should back off. It was an early attempt at preemptive traffic control to throttle back before something has to start dropping packets.
There's not a whole lot of equipment that sends them, but pretty much every OS I've come across honors the messages to some extent. I don't know if the cheap NAT routers that many people use pass them along or not, though NAT in general tends to be fairly broken when it comes to ICMP.
If a man in the middle were to spoof ICMP source quench packets that looked like they came from either of the p2p nodes that were communicating, the effect would be that they would start sending data more slowly to each other. The connection would still be open, they just wouldn't transmit as fast as they could.
After reading the article it became clear that what Comcast is doing is much more evil. They're setting RST flags on packets (or maybe spoofing new packets in the right segment range with it set), which causes the entire connection to abort rather than just be slowed down. It could cause a lot of grief if their filter misidentifies something as p2p and starts shutting down the connections, as apparently happens to Lotus Notes traffic.
That last link has some good packet dumps of it happening.
Nope. This has been discussed ad nauseum already, but Comcast (and Sandvine, which they are in all likelihood using) isn't looking at the actual data, it's looking at the overall pattern of traffic. It is still going to send RST packets, regardless of whether or not your connections are encrypted.
Sean Daugherty "I have walked in Eternity -- and Eternity weeps."
See if Earthlink offers cable Internet through your cable system. They do where I am. Earthlink has it's own gateways, etc. They have better policies. They allow low-bandwidth servers on a residential connection. And no, I don't work for them.