Dan Rayburn a watcher of the CDN (Content Delivery Network) industry and analyst for Front & Sullivan has pointed out that Apple appears to have switched to a dual provider setup.

Apple has for years used Akamai to deliver downloads from its website and over iTunes but Rayburn has noticed that some downloads have begun being delivered from addresses containing the llnw.net domain which belongs to Limelight Networks, arch rival to Akamai.

I saw this dual-vendor approach happening across many different pieces of content for Apple including OSX updates, application downloads from the Apple.com site (like the iLife trial) iPhones software updates and some apps for the iPhone app store.

I started noticing all of these changes around the November time frame and didn’t see a single piece of content being delivered for Apple, by Limelight, anytime before that.

Rayburn doesn’t appear entirely sure why Apple would begin using both providers but points towards Apple’s “crazy” growth associated with the iTunes and App Store.

“We already know that no CDN has unlimited capacity and can only handle so much traffic at any given time and if you are Apple, using more than one CDN is just smart business,”