Amazon has answered some of those questions in an FAQ and a longer terms and conditions document published last month. For instance, users will be able to browse using Silk without going through Amazon's servers, although that will presumably result in longer page rendering and download times.
Markey wasn't the only congressman to take on Amazon last week.
In a hearing last Thursday by the House Subcommittee on Commerce, Manufacturing, and Trade, Rep. Joe Barton (R-Texas) blasted Silk for its data collection potential.
"My staff yesterday told me that one of our leading Internet companies, Amazon, is going to create their own server and their own system and they're going to force everybody that uses Amazon to go through their server and they're going to collect all this information on each person who does that without that person's knowledge," said Barton during the hearing. "I mean, enough is enough."
Barton and Markey are co-authors of legislation that would update the Children's Online Privacy Protection Act.
Markey asked Amazon to respond to his questions by Nov. 4.
Amazon did not immediately reply to a request for comment on Markey's letter.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer or subscribe to Gregg's RSS feed. His email address is email@example.com.
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