Internet backbone operator Cogent has long expressed its displeasure with Comcast's demands for payment in exchange for accepting Netflix video and other traffic.

Comcast has argued that the data Netflix sends into its network creates an imbalance that should be rectified by payments from Netflix and its transit providers like Cogent. Netflix decided to pay Comcast—but Cogent has held out.

Today, Cogent CEO Dave Schaeffer made a different argument, saying that Comcast is the one who should be paying for connectivity. He did so while testifying in front of a House Judiciary Committee hearing on Comcast's planned acquisition of Time Warner Cable.

Schaeffer pointed to the fact that Comcast is not considered to be a so-called "Tier 1" network. There are a dozen or so Tier 1 networks that make up the closest thing the Internet has to a backbone. Tier 1 networks can reach every part of the Internet simply by peering with one another. Other networks buy "transit" in order to access the rest of the Internet. Peering is a point-to-point connection only, which doesn't necessarily guarantee passage of traffic to any networks beyond the two involved in the connection.

"Comcast does not operate a global network. In fact, it should be buying connectivity to the global Internet but has used its market scale and scope to extract an unusual concession," Schaeffer told members of Congress. "It wanted free connectivity, peering to the Internet, even though it didn't operate a global network. It didn't carry its fair load. Because it represented so many customers, backbone operators like Cogent and others agreed to peer with them. That wasn't good enough for Comcast. As Comcast's market power continued to increase and consumers had less choice, they actually started demanding payments for connectivity. A larger Comcast will be able to demand even greater payments."

While Comcast obviously doesn't buy transit from Cogent, it does purchase IP transit service "from Tata Communications in order to reach networks with which it does not have peering arrangements," according to economist Gregory Rose's 2011 analysis of a peering dispute between Comcast and Level 3. Rose pointed to a 2010 post by Internap network architecture manager Adam Rothschild, which said, "Comcast runs its ports to Tata at capacity, deliberately, as a means of degrading connectivity to networks which won’t peer with them or pay them money."

In some cases, Comcast actually sells transit. With Netflix, Comcast is receiving payment for peering only.

In today's congressional hearing, a joint written statement by Comcast Executive VP David Cohen and TWC CEO Robert Marcus said that "Comcast has a long record of working cooperatively with other companies on interconnection, peering, and transit."

"Importantly, no content provider is ever compelled to interconnect directly with Comcast’s or TWC’s ISP networks," the testimony said. "Comcast in particular has over 40 settlement-free routes and 8,000 commercial arrangements, which include dozens of substantial paid peering and transit arrangements with CDNs, ISPs, and major content providers which bring content to Comcast’s ISP network for delivery to Comcast’s customers. The overwhelming majority of content from across the globe comes into Comcast’s ISP network over its settlement-free connections with its peers, without the content provider having any direct relationship with Comcast. Those connections are always an option for every content provider, and they are always open—in fact, they are the lifeblood of Comcast's Internet business because they are also how Comcast gets its customers’ content to and from the rest of the world."

"The combination of Comcast’s and TWC’s ISP networks, which will account for less than 40 percent of the 'fixed' ISP market, will not come close to enabling the combined company to adversely affect competition in the interconnection market," the testimony also said.

Schaeffer claimed that Netflix was forced into signing a contract with Comcast. The cable company disagreed with that assessment, saying that Netflix's interconnection agreement with Comcast "is neither novel nor unusual. And, in fact, Netflix has recently followed up this direct interconnect agreement with a similar agreement with Verizon."

In a statement to Ars, a Comcast spokesperson said, “The backbone and transit markets today are very competitive and nothing about the Comcast/Time Warner Cable transaction changes that. Any issues in the transit market have nothing to do with this deal. For years, Cogent has been embroiled in disputes around the globe, from France, to Sweden, to China and here in the US with multiple providers. The company has a history of taking advantage of agreements and attempting to cry foul. This is no different from the business disputes they’ve had with ISPs and others for over a decade. Comcast has always been willing to enter into industry standard and commercially reasonable agreements with Cogent and similarly situated companies.”

Comcast also said that non-Tier 1 networks have built up enough backbone infrastructure that they don't necessarily have to buy transit anymore—instead, they can trade transit with Tier 1s. The Comcast/Tata arrangement is "not a straight paid transit deal," Comcast said.

Comcast argued that it could be considered a Tier 1 itself, as less than one percent of its traffic requires transit.

In a background call with Ars, a Comcast official also said that Comcast has settlement-free peering deals with all the Tier 1 networks. Although home Internet service is typically unbalanced with most traffic heading toward consumers, Comcast also carries streaming traffic for its subsidiary, NBC, and for many business customers including Web services, content delivery networks, and universities. This balances out Comcast's traffic exchanges with Tier 1 networks, with Cogent being the major exception because of how much Netflix traffic it carries, according to Comcast.

Merger would strengthen Comcast’s hold over programming, opponents say

Additional testimony in today's hearing brought up other competition concerns, including some regarding sports programming.

"A merged Comcast and TWC would have both the ability and incentive to withhold sports, entertainment, and other programming from other multichannel video programming distributors ('MVPDs') and harm competition," antitrust attorney Allen Grunes' testimony said. "The reduction in competition would lead to less pressure to control cable bills or to develop new offerings."

Grunes also said Comcast's proposed divestitures of customers won't ease harmful effects. "While the overall number of subscribers held by the merged entity would be lower as a result of system sales to Charter," Comcast will gain subscribers in New York and Los Angeles. "Comcast is not planning to shed subscribers in the most valuable markets. Further, the proposal does little to reduce the parties' share of the high-speed broadband market, which would remain well over 30 percent."

There was also testimony from Patrick Gottsch, founder and chairman of Rural Media Group, which operates numerous rural TV channels, including RFD-TV.

"Following its merger with NBCUniversal, Comcast dropped RFD-TV in all of Colorado and New Mexico," Gottsch said. "Because there is no clear business reason to understand Comcast's decision, we can only speculate that RFD-TV has become competitive with Comcast's affiliated programming."

Cohen countered that customers who want RFD-TV can switch to Dish or DirecTV.

Editor's note: The original version of this story incorrectly referred to David Cohen as Comcast's CEO.