AT&T: We don't throttle P2P traffic

In response to questions raised by BitTorrent-based client Vuze, phone company denies using forged reset packets to disrupt peer-to-peer file sharing traffic on its network.

Anne Broache Staff Writer, CNET News.com
Anne Broache
covers Capitol Hill goings-on and technology policy from Washington, D.C.
Anne Broache
3 min read

AT&T on Friday denied using forged reset packets to interfere with network connections of Vuze file-sharing platform users, as Comcast has been accused of doing with BitTorrent traffic.

The statement came in response to a report released earlier this week (PDF) by Vuze, which offers a BitTorrent-based client primarily used for distributing video. The start-up has asked the Federal Communications Commission to impose regulations prohibiting broadband operators from blocking or degrading peer-to-peer traffic.

Vuze's report claimed to document the median reset rates experienced by more than 1,200 "autonomous system numbers," which are unique identifiers for individual IP networks and routers, as monitored using a plug-in Vuze began offering last month. (It tracks all possible network interruptions, not just ones related to the Vuze platform.)

According to Vuze's data, a number of Comcast connections recorded the most frequent interruptions, but the top 20 highest reset rates also included users with Cablevision, BellSouth (an AT&T property), and AOL subscriptions.

Vuze said it planned to ask those Internet service providers to be more transparent about the cause of those reset packets and disclose whether they are using a "false reset message" technique. Meanwhile, it filed its preliminary report with the FCC, acknowledging that its results weren't definitive and that the documented disruptions could have occurred for a multitude of reasons.

AT&T bit back on Friday, denying using "false reset messages" to manage its network and arguing that Vuze's measurements were "misleading."

Here's a snippet from the letter:

In response to your specific question about AT&T's network management practices, AT&T does not use "false reset messages" to manage its network. We agree with Vuze that the use of the Vuze Plug-In to measure network traffic has numerous limitations and deficiencies, and does not demonstrate whether any particular network providers or their customers are using TCP Reset messages for network management purposes. Given that Vuze itself has recognized these problems with the measurements generated by its Plug-In, we believe that Vuze should not have published these misleading measurements, nor filed them with the FCC. Moreover, as Vuze and others have acknowledged, TCP resets are generated for many reasons wholly unrelated to the network management practices of broadband network providers, which explains why resets may appear on networks of companies such as AT&T who do not use TCP resets for network management.

Vuze CEO Gilles BianRosa sent CNET News.com the following response to AT&T's letter on Friday afternoon:

"Our data suggests that the reset rates for Bell South, which is owned by AT&T, were higher than for many other ISPs. Our data collection was credible and transparent, but not conclusive. Therefore, we decided that it was best to simply ask AT&T and others if they use reset messages as a network management technique. AT&T has now answered that they do not. We appreciate their response and hope all network operators will be as forthcoming. It is easy to debate methodology, but, given the shortage of facts and the gravity of the issues to our user base, it is difficult to criticize the asking of a fair question--what network management practices are you using?"

Comcast, of course, has admitted to delaying "excessive" peer-to-peer file-sharing traffic at "peak hours" of network congestion in the name of keeping the network running smoothly for all its users. In a report last year, the Electronic Frontier Foundation said it had conducted tests confirming that the company was using forged reset packets to throttle certain BitTorrent and Gnutella sessions.

Under fire from consumer advocates and investigation by the FCC, the cable operator has since pledged to migrate to a "protocol agnostic" network management technique by the end of the year.