A report by Germany's Max Planck Institute reveals that Comcast and Cox Communications are blocking BitTorrent traffic throughout the day, despite Comcast's claims that it only throttles BitTorrent Traffic during peak network hours. Comcast also claims that its throttling of BitTorrent traffic is imperceptible to its customers. It is likely true that most of Comcast's customers won't realize that degraded performance for BitTorrent transfers are occurring because Comcast is actively throttling that traffic.
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Cox, Comcast Accused of More BitTorrent Blocking
By Roy Mark
May 15, 2008
eWeek.com