A Pyrrhic Victory Faces Either Side in the Cable Access Controversy

by Andy Oram
July 23, 1999

The fight over cable modems has eclipsed the Microsoft cases as the anti-monopoly debate wrapping up the millennium. Both sides in cable access are talking competition. TCI and MediaOne, now owned by AT&T, point out that their cable modem service enhances competition by scaring the Bell telephone companies into better pricing and service. But ISPs left out of the loop call cable modem service a threat to competition because it channels all users through the cable company’s chosen ISP, Excite@Home or Road Runner.

A closer look at cable modem service suggests that both sides are bound for disappointment. Cable modems are great for the first few people who sign up in each neighborhood, but speed declines quickly on the shared medium. Cable companies already walk a promotional tight-rope, one hand outstretched to offer their Internet access, but the other thrust forward to warn users not to expect to fully exploit the advertised speed, and imposing terms of service that squelch bandwidth hogs.

Can Open Access Be Offered?

A lot of debate has revolved around whether competition is technically possible over cable. GTE and Knology (a telecom-owned networking company in the South) have both done it, although details on their methods are sparse. Canada has ordered its providers to do it. David Devereaux-Weber of the University of Wisconsin says his site has been offered direct access to the cable network. Let’s look at three proposed solutions.

In order for the cable company to deliver its services, the distribution center, called the head-end, contains a router called a Cable Modem Termination System. This CMTS usually takes its television content from a satellite transmission and its Internet traffic through a traditional line. Traffic travels from the head-end to subsidiary nodes serving about 200 users each, and on to individual users.

One channel is reserved for data traffic, and cable modems are tuned to the frequency of this channel. All user requests travel down this shared frequency—the key technical limitation of the cable network and the reason for bandwidth saturation—to the CMTS, where they are converted to IP packets and routed to the Excite@Home or Road Runner server.

One way to provide competition is to give each ISP its own CMTS. That would require either a separate TV channel dedicated to each ISP, or an enhancement to the cable data standard (Data Over Cable System Interface Specification, or DOCSIS) to allow a CMTS to route data meant for a different ISP to another CMTS.

A second solution is more practical: make the CMTS route data to the proper ISP. By checking the source address, a CMTS can determine which user is making the request and match him up to his chosen ISP.

A third solution places even less of a burden on the cable company. The user’s system is configured to connect to an ISP and create a tunnel through the CMTS, as in a virtual private network. The cable company doesn’t have to do anything at all, and presumably has no say in the matter.

Right in Principle

Open access is philosophically on target. Its advocates have in their camp such reputable activists as the Consumers Union, the Media Access Project, and my own organization, Computer Professionals for Social Responsibility; they’ve even won praise from the Economist magazine. The public interest groups are grouped in an organization called No Gatekeepers, while ISPs fighting for a place on the networks are in the OpenNET Coalition. A bill in favor of open access has been introduced into Congress. And some cities, led by Portland, Oregon, have refused to renew cable franchises without open access.

Cable companies worry public advocates because of the trouble that potentially comes from combining carrier and content. AT&T’s first argument—that they need to control the portal in order to make their investment pay off—does their cause more harm than good. One has to deduce that they plan to manipulate people to stay on Excite@Home instead of sampling the diverse offerings of the Internet; their approach smacks of the cable companies’ perennial role as content providers.

Unfortunately, the vision offered by competing ISPs dissolves when you hold a magnifying glass up to it. Such spokespeople as Charles Brewer of MindSpring promise better terms of service and better customer support. But there’s little that can be done about terms of service; when the cable companies ban servers and place limits on streaming downloads, they’re not trying to be Blue Meanies but just recognizing the natural limitations of the cable network. As for customer support, since all traffic still passes along the cable network, the cable company is still the prime culprit when something goes wrong.

Regulatory headaches

The strongest argument on the cable companies’ side is the nightmare that competition would provide to regulators. Fifteen years after the break-up of AT&T, the FCC is still arguing with the Bells about how to offer equitable competitive access. Vats of ink have been spilled on such questions as fair pricing for bottom-layer services, non-discriminatory hook-ups and trouble-shooting, and how to share limited resources. Imagine throwing the cable companies into a similar maelstrom.

No wonder the FCC has failed to back open access. In fact, many lawyers have argued persuasively that current laws preclude the FCC from forcing open access on cable carriers as they do the incumbent telephone companies.

Even darker suspicions have circulated. Many telecom activists claim that the cable modem issue is merely a distraction from the key task of opening the local Bell telephone networks. Since cable modem users are only about 2% of the Internet market, dominance is a threat only if huge numbers flock to it—and that’s not likely to happen because of bandwidth limitations.

What if the competing ISPs won the regulatory battle and started marketing cable modems to all their customers? They would quickly max out the existing network, and upgrades would be just as costly as in any other medium. The only cheap way to increase bandwidth would be to set aside multiple channels, an unappealing choice for the cable companies because they’d be sacrificing premium content or advertising-rich TV programs. So while the ISPs hold the moral imperative, those who grab hold of cable will find it comes up short.


Andy Oram is an editor at O’Reilly Media. This article represents his views only. It was originally published in the online magazine Web Review.