The product would also have some limitations if it rolled out for general availability, but for its capability to filter the large quantities of unseen tracking cookies regularly served up across the Web, it better comports with a reasonable understanding of privacy, according to Anderson.
"It creates a Web that reflects users' expectations," he said.
"Trust is the true currency that needs to be protected. The lack of trust stems from users not understanding the value proposition of online tracking. This is where industry can really make a difference -- if users don't understand what happens to their data, how it is used, or the tradeoffs, they will inevitably seek more protective blocking options," Anderson added. "We also know that legislating technology is risky. Given the current environment, though, it is clear that more is required, including continued congressional oversight."
Who Can you Trust?
So the DAA accuses Microsoft and Mozilla of breaking the deal the parties reached at the White House, while Mozilla's Anderson said that the do-not-track signals users send through their browser "are largely ignored by the ad networks."
The legislative backdrop of Wednesday's hearing is a bill that Rockefeller introduced earlier this year that would establish mechanisms for implementing and responding to do-not-track, making that browser feature the law of the land. Rockefeller, who has announced that he will not seek reelection next year, introduced a similar bill in the last congress.
More immediately, the World Wide Web Consortium (W3C), a standards body, has been convening a working group of stakeholders to develop technical specifications for do-not-track, next plans to meet in California in May.
The W3C's work on the do-not-track standard has been slow, a delay the various parties -- notably the advertising representatives and browser makers whose views got an airing at Wednesday's hearing -- have explained with mutual accusations that their adversaries are negotiating in bad faith.
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