It's not a secret that DVD rental company Netflix has parts of its technology infrastructure running on Amazon's cloud (the New York Times just wrote about it last month), but Amazon is now giving more details. According to information released by Amazon today, Netflix has been using Amazon Web Services for more than a year "for both customer-facing and backend applications" and is now "expanding the set of applications that it is migrating" to Amazon's cloud.

It's an interesting partnership given that Netflix and Amazon are competitors in the streaming video market and Amazon has long been rumored to be interested in acquiring Netflix.

Amazon says Netflix will be using its web services to power member movie lists, website search, movie transcoding, and its recommendation system. More from Amazon:

Delivering content to members faster and on more devices: Netflix is utilizing the Amazon Elastic Compute Cloud (Amazon EC2) and Amazon Simple Storage Service (S3) to transcode and store the movie subscription service's growing movie content library for delivery on new platforms, including the Nintendo Wii and the Apple iPad. The flexibility and scalability of AWS allows Netflix to utilize vast numbers of servers to transcode and store TV episodes and movies into new formats quickly, and AWS pay-as-you-go pricing ensures that Netflix pays only for resources used. Netflix can do all of this without being exposed to the costs and burden of maintaining large amounts of infrastructure that go underutilized.

Maintaining a highly available and resilient member-facing website: Netflix runs several of its website application functions on AWS, and is rapidly migrating more of these components to AWS. The important functions migrating to AWS include the delivery of movie and member metadata within the Netflix website. Using this data, Netflix is able to continue developing a more accurate recommendation engine, ensuring that Netflix members receive the TV episodes and movies they want, when they want them.

Analyzing data to improve streaming quality: Netflix is using Amazon Elastic Map Reduce to analyze streaming sessions and extract business metrics around performance, viewing patterns and more, which enables Netflix to continue to improve the quality of streaming.

Amazon is trying to interest big companies in its cloud computing services — and clearly hopes the Netflix example will bring in more business. (Amazon is targeting government agencies as well).

It will be interesting to see if this Amazon-Netflix cloud partnership develops into something more.

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