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Google Caught in Comcast Traffic Filtering?

marcan writes "Comcast users are reporting 'connection reset' errors while loading Google. The problem seems to have been coming and going over the past few days, and often disappears only to return a few minutes later. Apparently the problem only affects some of Google's IPs and services. Analysis of the PCAP packet dumps reveals several injected fake RSTs, which are very similar to the ones seen coming from the Great Firewall of China [PDF]. Did Google somehow get caught up in one of Comcast's blacklists, or are the heuristics flagging Google as a file-sharer due to the heavy traffic?"

6 of 385 comments (clear)

  1. iptables fake RST detector by EmagGeek · · Score: 5, Interesting

    use connection tracking on this one:

    iptables -I INPUT -j LOG -p tcp -m tcp --tcp-flags RST RST -m conntrack --ctstate NEW,INVALID

    The fake RST will probably not have a valid sequence number for the established TCP connection, so the Linux stack will flag it as a NEW connection, and the fact that you're getting a RST for a NEW connection should be good enough alarm.

    Or maybe it would also work with just the matching code

    iptables -I INPUT -j LOG -p tcp -m tcp --tcp-flags RST RST -m state --state NEW,INVALID

    What do y'all think?

  2. Push it one step further... by KingSkippus · · Score: 5, Interesting

    What if Google, a (justifiably) huge advocate of network neutrality, is deliberately sending the type of RST packets that imitate Comcast's faked packets, specifically to Comcast IP addresses, knowing the inevitable fallout that would result? It would make an already bad situation for Comcast far, far worse, and it's likely that the requested Senate investigation would turn into nails in the coffin for those who want preferential treatment of packets on the Internet.

    For a company that does no evil, if they could pull it off, it would be absolutely diabolical. But then, it could easily be one of those "ends justify the means" kinds of situations. At any rate, all I can say is "MWAH HAH HAH HAH HAH!!!! Suckers!"

    (No, I don't actually believe that's what's happening, but man, what an AWESOME plan to make network neutrality happen once and for all.)

  3. going on for months with google maps by Trailer+Trash · · Score: 5, Interesting

    I have been unable to use Google maps for months now on Comcast. I have called them, but, you can guess how that went. Yahoo maps and Mapquest work fine, but on Google I get about half the tiles filled in before it stops. And I mean it stops. It ends up looking like a checkerboard. Occassionally it will finish a couple of minutes later, but typically it never does.

    Getting Comcast to fix it seems unlikely.

  4. Go even further and ignore fake RST? by SIGBUS · · Score: 4, Interesting

    This looks like it could be extended - add a -j DROP rule after the -j LOG (log the offending packet, and then send it to the bit bucket).

    --
    Oh, no! You have walked into the slavering fangs of a lurking grue!
  5. Re:unfair competition by Shakrai · · Score: 4, Interesting

    That's an interesting take on it. And as far as I'm aware there is no DSL provider in the United States doing anything like this. It certainly seems to be the case in the wireless world. The carriers removing or blocking features that may compete with their own content offerings.

    One wonders what the solution to this is. Prohibit someone from being in the content business AND the delivery business at the same time? They'd fight you tooth and nail on that -- and you'd have the "free market" types after you as well.

    In any case I think they will shoot themselves in the foot in the long run. What happens when all P2P traffic is encrypted and looks like any other encrypted protocol (ssh, ssl, etc)? At that point you may be able to identify WHICH subscriber is using p2p (bittorrent stands out like a sore thumb for the sheer volume of connections it establishes) but how will you identify which individual packet is p2p and shape it? Or will they just start sending random RST packets to ALL your connections, including (as TFA suggests) Google?

    If bandwidth IS the issue then in the long run they only have two options. Invest in some upgrades or stop selling "unlimited" service. Personally I'd take the best of both worlds. I'd offer a "premium" package aimed at p2p users (no monthly bandwidth limit and/or higher speeds) and use the money from that to expand my network.

    --
    I want peace on earth and goodwill toward man.
    We are the United States Government! We don't do that sort of thing.
  6. Re:Not me... by Drachemorder · · Score: 4, Interesting

    I'm on Comcast and I do notice some unusual "connection reset" errors every now and then. More than I would normally expect, at least. They happen when I'm trying to telnet/SSH into my Linux box from outside, when I try to download something on Steam, in fact during nearly anything that requires a connection to be established for any significant period of time. I never used to have this problem before Comcast assimilated my previous cable provider. Makes me wonder if it's deliberate.