Comcast, which underwent heavy criticism last year for blocking file-sharing services like BitTorrent, has reportedly been caught quietly changing its Terms of Service. Although Comcast has denied that they interfere with P2P, even in light of mounting evidence of the contrary, the new TOS notably acknowledges the use of “reasonable network management practices that are consistent with industry standards.”

“Industry standards.” A phrase like that kind of makes you wonder what other ISPs are doing, doesn’t it? We examined the Terms of Service of several of Comcast’s biggest competitors and found that provisions allowing interference with P2P traffic seems to be a standard part of ISPs’ legal boilerplate these days. And unlike Comcast, the competition is not shy about describing exactly what they want to do to stop P2P on their networks.

Comcast has been in the spotlight since reports about its interference with BitTorrent traffic first surfaced last summer. The company keeps denying any wrongdoing, but multiple tests have shown that they are in fact messing with their subscribers’ BitTorrent traffic. Other ISPs have been a little more forthcoming about the subject all along.

Fellow cable ISP Cox, for example, has made no secret of the fact that it’s blocking P2P traffic as well, so we weren’t too surprised to find this abstract in the company’s Subscriber Agreement: “Cox reserves the right to manage its network for the greatest benefit of the greatest number of subscribers including, without limitation, the following: rate limiting, rejection or removal of “spam” or otherwise unsolicited bulk email, anti-virus mechanisms, traffic prioritization, and protocol filtering.” And no, this is not just about commercial spammers, but about interfering with your day-to-day use: “You expressly accept that such action on the part of Cox may affect the performance of the Service.”

Time Warner subsidiary Road Runner, on the other hand, hasn’t been found to be messing with BitTorent traffic yet, but it seems to be considering this option, judging by its Acceptable Use Policy: “Operator may use various tools and techniques in order to efficiently manage its networks and to ensure compliance with this Acceptable Use Policy (“Network Management Tools”). These may include detecting malicious traffic patterns and preventing the distribution of viruses or other malicious code, limiting the number of peer-to-peer sessions a user can conduct at the same time, limiting the aggregate bandwidth available for certain usage protocols such as peer-to-peer and newsgroups and such other Network Management Tools as Operator may from time to time determine appropriate.”

Road Runner must use the same law offices as fellow ISP Charter, whose Acceptable Use Policy is virtual identical, including the option of “limiting the number of peer-to-peer sessions” and “the aggregate bandwidth available for certain usage protocols such as peer-to-peer.” Charter did however update its policies recently, adding a very telling sentence: “Charter may employ traffic-management technology, including but not limited to packet-reset technology, which technology may materially slow the uploading of certain files.”

This “packet-reset technology” mentioned by Charter is exactly the man-in-the-middle attack Comcast has been using to disrupt BitTorrent: Devices used by the ISP pretend to be the actual user and send a reset message to the BitTorrent clients of fellow file sharers, canceling uploads and thereby considerably slowing down download speeds. Comcast is reportedly using equipment from Sandvine to do this, and Sandive has been claiming that that “eight of the Top 20 broadband service providers in the U.S. are Sandvine customers”, as Om reported earlier.

To be fair: It’s not certain whether Charter actually makes use of these techniques, but the mere fact that virtually all major U.S. cable ISPs reserve the right to interfere with their users’ access to services like Vuze, Pando and BitTorrent.com could give the net neutrality debate new urgency.