The secret to Amazon Silk browser’s speediness? WebKit and SPDY.

Amazon yesterday outed its Kindle Fire tablet, the lower-priced $79 Kindle and the new $99 Kindle touch. They also unveiled a brand new browser written exclusively for the Kindle Fire, dubbed Silk. There has been some concern among web developers about the browser’s rendering engine given how numerous web sites are optimized for the open-sourced WebKit rendering engine. According to a post by Mike Mainguy, a software architect with Lemans Corporation, the Silk browser does leverage WebKit as its rendering engine. Moreover, it also employs SPDY, Google’s optimized hypertext transfer protocol introduced in late 2009 as part of the search giant’s “Let’s make the web faster” initiative. It’s currently used in Chrome and now in Amazon’s Silk browser, too. Mainguy explains:

All told this isn’t as big a technological change at the front end and is more of a story about amazon trying to use their infrastructure to make the mobile browsing experience better.  Frankly, this is a scaled up and modernized version of what blackberry did years ago (are they still doing that?).

It appears that Amazon combined SPDY with Amazon Web Services to caches files and offload page rendering to the cloud, depending on workload. According to the Silk team:

All of the browser subsystems are present on your Kindle Fire as well as on the AWS cloud computing platform. Each time you load a web page, Silk makes a dynamic decision about which of these subsystems will run locally and which will execute remotely. In short, Amazon Silk extends the boundaries of the browser, coupling the capabilities and interactivity of your local device with the massive computing power, memory, and network connectivity of our cloud.

Rather than open multiple network connections, SPDY facilitates a single connection between the server and the user’s browser. The protocol is optimized to intelligently deliver the files that make up web pages while allowing web developers to prioritize more important pieces like the user interface code and graphics over article images (more technicalities here). WebKit has become the de facto standard rendering platform for the web. The project is being used in Google’s Chrome, Apple’s Safari and the vast majority of mobile browsers.