The browser will determine whether to download the mobile or the static version of any given website, based on the capabilities of the hardware, as well as the richness of the site itself. "It learns effectively as you're browsing to get the best possible version of the content to you," Jenkins said. This works particularly well on popular sites, where many of the common elements can be cached.
HTTP is replaced with SPDY
Amazon also sped operations by doing away with the HTTP protocol, which is normally used to convey Web pages from the server to the user. The HTTP protocol "is not the most efficient protocol of the modern Web," Jenkins said. "It doesn't multiplex content well -- it is hard to get a bidirectional flow of content." As an alternative, Silk uses a variant of the Google SPDY protocol. HTTP is still used between the content provider and EC2.
Amazon dismisses privacy fears
Of course, the fact that all the user's Web browsing is being directed through Amazon will raise the interest of privacy advocates, who might see the technology as invasive. Jenkins denied that Amazon would be doing any personal traffic analysis, though. "There is no personal information stored on the EC2 at all," Jenkins said. He also noted that it is possible for users to turn off the EC2 service altogether and use the browser in a standard way.
The company also spent a lot of time making sure that one user would not accidentally be served another user's content when checking popular sites such as Facebook. "Some of the earlier efforts that other companies made at this did result in that. So we thought very very carefully about that. That was just unacceptable as an outcome."
Amazon's approach to the tablet is an "interesting spin" in a cluttered market, one analyst said. "While the split browser architecture is not new, Opera having been a player for a couple of years, I find the overall strategy to be an interesting spin on the me-too Android software we have seen so far, and possibly a game changer," noted Al Hilwa, IDC analyst for applications development software. "In one fell swoop Amazon harnesses its commanding lead in cloud services, the content richness of a leading online retailer and its successful Kindle business strategy to deliver what might become one of the most effective antidotes to the mobile bandwidth crunch."
The Kindle Fire uses smartphone-oriented Android 2.3 "Gingerbread" OS with a heavily customized interface. Amazon had no immediate plans to port Silk for other platforms, Jenkins said.