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Beating Comcast's Sandvine On Linux With Iptables
HiroDeckard writes "Multiple sites reported a while ago that Comcast was using Sandvine to do TCP packet resets to throttle BitTorrent connections of their users. This practice may be a thing of the past as it's been found a simple rule in the Linux firewall, iptables, can simply just block their reset packets, returning your BitTorrent back to normal speeds and allowing you to once again connect to all your seeds and peer. If blocking the TCP packet resets becomes a common practice, on and off of Linux, it'll be interesting to see the next move in the cat-and-mouse game between customers and service providers, and who controls that bandwidth."
Wasn't this solution posted in the first few comments when this was first reported as happening.
Here's a link to Google's cache of the article.
Not just that, but it filters out RST packets that may in fact have been sent by the peer. So this trick can leave you with sockets hanging open in a bad state.
I noticed my WoW connection suddenly became unstable at the beginning of the month.
I implemented similar firewall rules on my mac and the instability was cut in half.
Guess the other half is being forged to the blizzard servers.
VLC FOR MAC IS DYING! IF YOU DEVELOP, PLEASE SAVE IT!!
I've had this command in my WRT54GL running DD-WRT for a while: iptables -A INPUT -p tcp --dport 39984 --tcp-flags RST RST -j DROP just replace 39984 with whatever post you use for bittorrent
I blame geof's speakers.
As my subject says. This is why you only put the filter on the specific port you are using for P2P traffic. For instance, my rule is as follows:
iptables -I FORWARD 3 -p tcp --dport 36745 --tcp-flags RST RST -j DROP;
The above does what it says, drop TCP RST packets on port 36745. That is all you need to do to keep it from affecting your other network applications which may be getting legit reset packets.
We were all warned a long time ago that MS products sucked, remember the Magic 8 Ball said, "Outlook not so good"
"Here;s an idea: Stop fucking stealing shit !! If you don't steal you won't care if your stealing facilitation enablers get a fucking RST or not. "
rst hurts anyone trying to keep long lived tcp connections, regardless of how much or what traffic they are sending.
Not sure what you mean by sending work email from home.
If you mean your ability to establish a connection with a corporate mail server not located on your ISP's network, then port 25 is unnecessary. You should use port 465 with SSL instead. Problem solved since no ISP ever blocks port 465 in any direction. At least not that I am aware of.
If you mean your ability to run a mail server at your house, then your shit out of luck period. There are a large number of mail servers now that use policy block lists. Every ISP publishes their policy block lists which includes your IP address range. The moment your mail server tries to establish a connection to another mail server using this block list your packets could be dropped right at the router, or your connection terminated by the mail server itself.
Now as upsetting as that might be, it really is for the greater good. The vast majority of all the SPAM being sent every day comes from compromised windows machines on dynamic IP address ranges. Using the policy block list is very effective at immediately stopping those communications from ever reaching the mail server.
If you are absolutely determined to run your own mail server from home I would suggest getting a static IP address. Not only will port 25 not be blocked, but you will have a MUCH BETTER chance of your packets not being dropped by routers servicing the mail servers you will be sending email to.
Another option, depending on the amount of money you want to spend, is to retain the services of an email services provider. There are more than a few out there. You can use your own domain and they will host it for you. They can also provide a fair amount of security and usually are more reliable in getting the email to the destination.
Additionally, you could always get a virtual server someplace and run your own mail server software on it. They have linux and microsoft systems available pretty cheaply. Then you would be operating on IP address ranges used by big ISPs and data centers.
Um, in the US, we're already paying for it. We have since the late 90's when congress passed huge tax breaks on to telcos to develop our 40Mbps connections - you have one of those don't you? The telco's promised us one years ago, I'm sure mine is just around the corner.