For a number of reasons, including ISP ad campaigns, the US broadband market has developed such that unlimited bandwidth is regarded as a universal right. With the advent of heavy P2P traffic, demand for music and video, and increased penetration, that "right" has left ISPs in the uncomfortable position of having overpromised their network capacity and scrambling for ways to avoid paying for greater capacity. Comcast's varied—and often awkward—attempts to come to terms with P2P usage represent a case study of this scramble, and word has it that the company is trying yet another new strategy: a bandwidth cap with some significant costs for users that exceed it.

Comcast, like many other ISPs, has a usage policy that contains nonspecific warnings against generating excessive Internet traffic, but never defines what excessive is. Since last year, it has grown increasingly aggressive about cutting down on the bandwidth used by its subscribers. Tactics started with going after the highest-volume users of its service, and suggesting they needed to pay for higher levels of service. But the company really grabbed the spotlight once word slipped out that it was throttling P2P traffic, a practice that drew the ire not only of its users but, more significantly, the FCC.

Since then, the company has sent out spasms of mixed messages. It argued that the FCC had no authority to block their process, but still decided to stop interfering with P2P traffic anyway. The company also joined in with other ISPs in trying to devise a P2P user's bill of rights and contemplated the use of P4P software.

But, as Nate Anderson recently detailed, the problem isn't access to sufficient capacity for the ISPs, but that adding that capacity costs money. Given that reality, the recent move by Time Warner to experiment with charging users for exceeding a well-defined bandwidth cap was almost refreshing in its honesty: no vague terms of service, and an obvious forwarding of the ISPs costs on to its consumers.

By these standards, it appears that Comcast may be ready to experiment with a little honesty, too. Broadband Reports is quoting an internal Comcast source that suggests the company is considering a bandwidth cap of 250GB per month, with users that go over the cap being charged $15 for every 10GB in excess. Comcast spokesman Charlie Douglas confirmed this report, saying, "Comcast is currently evaluating this service and pricing model to ensure we deliver a great online experience to our customers." For now, however, he emphasized that no final decisions have been made.

As Eric Bangeman noted in his analysis of Time Warner's decision, honesty will only get the cable companies so far. Although they rarely compete with each other, Verizon and other phone companies would be happy to accept their customers, and some wireless broadband technology on the horizon may increase the competition further. Users may be even more likely to switch service providers if these bandwidth charges, instead of covering the cost of capacity, serve to increase corporate profits.