"We generally do not keep this information for longer than 30 days," said Amazon.
"Amazon is familiar to consumers as an e-merchant, but [Silk's connection to EC2] is really drastically different," said Brauer-Rieke.
Users will, however, be able to run Silk without the connection to Amazon's servers if they want, the company confirmed in its FAQ.
"It was a great move to include that option," said Brauer-Rieke. "It shows that they understand the privacy implications."
What will be crucial, Brauer-Rieke continued, is how Amazon explains this new technology and its consequences to consumers. "They're going to need to inform people about this fundamental change in their browsing," he said. And how they do that will be where the privacy rubber meets the road.
The Electronic Frontier Foundation (EFF), another digital privacy advocacy organization, declined to comment in detail on Silk, but a spokeswoman acknowledged that the group "think[s] there are some worrisome privacy issues," including those revolving around browsing history.
"We'll definitely be following the developments, as browser history is very sensitive information, including data about your interests, your concerns, and your private life," the EFF spokeswoman said in an email Wednesday.
Brauer-Rieke kept returning to the similarities between Silk's link to Amazon's servers and the traditional role of ISPs.
"This is ultimately like an ISP," he said, "but at the same time, ultimately more ambitious. Will consumers understand that?"
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