After months of rumors and speculation, Apple revealed the long-awaited iCloud last week. The free service replaces MobileMe for $99/year, and, considering of all the new features, it’s expected to be quite popular.

iCloud is available to all Apple account holders, which Apple estimates to be in the 200 million range. So how can iCloud withstand all that traffic? Aside from their massive NC data center and 12 petabyte digital locker, Apple appears to be using rival cloud services…

Infinite Apple received an interesting tip earlier this week that Apple’s iCloud service was somehow utilizing the cloud services of arch rivals Amazon and Microsoft.

The source came across the data after setting up a Charles, also known as an HTTP monitor, on an iPad to peek at the HTTP traffic of an image sent through iMessage. The tipster sent in multiple screen shots of the find.

“icloud.com provides some sort of authentication to a windows.net address, and then sends a confirmation back to iCloud. Image downloads come from an s3.amazonaws.com address.”

As the site points out, Apple is more than likely using these services as some sort of CDN, rather than to support the entire iCloud structure. A CDN is a content distribution network, and helps increase access bandwidth and reduce latency.

It’s interesting, though, that with all of Apple’s resources it still chose to use its competition’s web services. Perhaps this is just temporary while work on Apple’s own data center and cloud network are completed.

We all know how temperamental Amazon’s servers can be, and Microsoft doesn’t have the best history as far as cloud services go, either. So would Apple really depend on these 2 companies for support when iCloud and iOS launch in the fall? I doubt it.

What do you think?