"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. So, if you are tired
of Sandvine (the application used by Comcast to throttle Bit
Torrent with fake TCP packet resets) screwing with your BitTorrent
and a user of GNU/Linux, then this is for you. I will tell you how
to take your bandwidth back..."