iCloud Mystery: Is Apple Using Azure & Amazon?

Early users of Apple's iCloud technology have uncovered a bit of a mystery: evidence that Apple may be using Windows Azure and/or Amazon Web Services in its early implementation of the iCloud. The reports are based on user analyses of HTTP traffic, and have prompted debate about what the data reveal and whether or not Apple is using other cloud services to supplement its North Carolina data center. Here's a recap:

On June 7 the Infinite Apple blog published screen shots of iCloud HTTP traffic analysis that indicate the use of the Windows Azure OS and images being called from Amazon's S3 cloud storage service. "We presume that iCloud isn’t entirely based on these other cloud services; it would be much more reasonable to deduce from these images that the other services are being used as some sort of CDN to take the load off of Apple," wrote Parth Dhebar from Infinite Apple.

On June 10, GigaOm mentioned the Infinite Apple report, but cast doubt about its conclusions. "We ran the screenshots by three networking and cloud experts at major companies," the story noted. "All three said that the screenshots did not conclusively show how iCloud was utilizing the Amazon and Microsoft technologies, if at all. Two sources said that the log could simply show that the image sent over iMessage was itself initially hosted on Azure or Amazon. A third source said Apple may be using Azure and AWS for content delivery network (CDN) purposes."

Infinite Apple responded on June 13 with additional testing, which it claims provides confirmation that iCloud is using the Azure BLOB (Binary Large Object) storage service. "The resulting traffic showed, quite clearly, the use of Azure services for hosting purposes," the story notes. "We don’t believe iCloud stores actual content. Rather, it simply manages links to uploaded content."

This week the story was picked up by prominent Microsoft-watcher Mary Jo Foley, who sought answers from the companies. "I asked Microsoft for comment and was told the company does not share the names of its customers," Mary Jo writes. "I asked Apple for comment and heard nothing back."

What's the significance? The leading theory is that Apple may be tapping the Windows Azure Content Delivery Network, which stores copies of user content on its network of 24 caching nodes around the globe.

If true, that would raise another question: what's up with Apple's relationship with its CDN vendors, which are led by Akamai Technologies (AKAM)? Dan Rayburn, who tracks the content delivery industry, recently offered his thoughts on what the iCloud might mean for Akamai. His conclusion: The iTunes component of iCloud is unlikely to be a huge business driver. "The bottom line is that the delivery of audio content from iCloud is not worth that much to Akamai or any other CDN," Dan writes. "The other services around iCloud could be worth more and if iCloud ends up supporting video content down the road, then the value of the delivery business would be much higher."