Comcast's move to limit its broadband customers' throughput to 250GB per month starting in October might anger those who want unlimited access, but it's actually good for privacy. Because the cap applies to all traffic equally, it doesn't require that Comcast snoop for particular types of application data. Contrast that with its previous (and initially undisclosed) practice of interfering with peer-to-peer traffic (in an effort to limit customers' downloading of huge, bandwidth-hogging files). The ISP says less than 1 percent of customers will be affected.

Of course, there's nothing to stop broadband companies from snooping in other ways. AT&T, for example, said earlier this year that it's investigating ways to dig deep into its customers' Internet traffic in search of copyrighted material, according to the New York Times. Meanwhile, AT&T is still getting flack because of its alleged spying on Internet traffic for the National Security Administration, without warrants.

The fight between Comcast and the FCC isn't over yet, either. In August, the FCC ruled that Comcast had violated federal policy by interfering with P-to-P traffic, and mandated that it stop doing so. In early September the service provider appealed the ruling. If Comcast is ultimately successful in overturning the agency's ruling, the company's customers could be capped and snooped on.

A usage cap can be applied poorly, too. Time Warner Cable, for instance, is testing a system in Beaumont, Texas, that applies caps and overage charges--its Internet access plans look a lot like cell phone plans. Time Warner customers choose plans that range from $30 per month for 5GB and a 5Mbps connection to $55 per month for 40GB and a 15Mbps connection. Considering that nifty but high-bandwidth online services such as Mozy backups and Netflix movie streaming could easily push someone over 40GB in a month, let alone 5GB, I really don't like Time Warner Cable's idea, to put it mildly. To my dismay, Comcast says it's "very interested" in seeing how the Beaumont trials turn out, and that it might move toward such a model in the future.

Faced with such alternatives, I would be content if ISPs were to stick with applying high usage caps that don't affect the majority of people and don't require invading anyone's privacy.

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