Silk, which is based on the open-source WebKit engine, connects to Amazon's cloud service and servers by default. The service will handle much of the work of composing Web pages, pre-rendering and pre-fetching content, and squeezing the size of page components, a way, claimed Amazon, to speed up browsing on low-powered devices like the Kindle Fire.
The data sent from and received by Silk, in other words, passes through Amazon's systems, giving the e-tailer an opportunity to extensively monitor the traffic in general -- Amazon has sworn it does not associate data with a specific Fire user -- and mine that for browsing behavior. For instance, Silk logs each website URL and by necessity transmits that to Amazon, which retains that data for 30 days.
Markey did not say when he would ask for more answers from Amazon about Silk.
Amazon has been coy about Kindle Fire sales, saying on Monday only that the tablet is the company's best-selling product but not releasing sales figures for last week's Black Friday.
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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