NEW YORK, NY — Comcast is standing by its story that it uses reasonable methods to control traffic on its networks, comparing its methods to those used to manage freeway traffic.On Tuesday, the broadband internet service provider filed an 80-page report with the U.S. Federal Trade Commission in which it gave a detailed explanation of its traffic-management techniques. The report named BitTorrent, a peer-to-peer file-sharing protocol, as the prime culprit in network slowdowns, but Comcast denied it blocks traffic associated with the protocol. It also denied it discriminates among other applications or service providers.

As the second-largest ISP in the U.S., Comcast provides service to more than 13 million subscribers. It said network management tactics are essential to prevent network congestion and provide acceptable service to all of its customers, not just the relative handful that tend to snarl traffic by monopolizing the majority of the available bandwidth.

Comcast delivered the report in response to an FCC inquiry brought about by consumer groups who allege the ISP gives preferential treatment to some kinds of traffic in violation of a concept known as “Net neutrality.” The FCC’s investigation of the ISP is seen by many pundits as an opportunity for the agency to demonstrate its dedication to the principle, to which it has given lip service in the past. FCC regulations currently prohibit network operators from blocking traffic entirely, but there is room for interpretation about how far ISPs can go in their attempts to manage their networks “reasonably.”

“Simply stated, there is nothing ‘neutral’ about a network that is not managed,” Comcast said in the filing. “An unmanaged network simply means that users who make disproportionately resource-intensive demand on the network can crowd out fellow users.”

Comcast compared its network-management strategies to metered-access freeway onramps.

“One would not claim that the car is ‘blocked’ or ‘prevented’ from entering the freeway, rather, it is briefly delayed, then permitted onto the freeway in its turn while all other traffic is kept moving as expeditiously as possible,” the company’s filing said.

In response, a BitTorrent spokesperson said instead of throttling traffic, Comcast should upgrade its systems in order to increase the available bandwidth on its network.

Comcast’s practice of selectively throttling traffic is “like putting a Band-Aid on the problem to achieve a short-term fix,” BitTorrent co-founder and President Ashwin Navin told Reuters.