iCloud Patent Different Than Expected
Wading through the recently uncovered iCloud patent an interesting tid bit emerges. In the patent there is the option to "Sync partial music."
This feature likely refers to the "local caching" of music stored on Apple's cloud based servers. What this means is when a playlist or group of songs is synched to your iDevice a small portion of each song, usually the beginning, is stored locally on the device while the rest of the song is then streamed from the cloud.
While this might seem to defeat the entire purpose of cloud based storage, with today's wireless speeds local caching is necessary for all cloud based services. The small amount of locally stored data allows users to jump between songs without waiting for them to buffer and load eliminating lag. This provides the user with the illusion that all of the songs are stored on the device. Local caching is what Spotify has been doing this since 2008. Pandora, Slacker, and other cloud based music services have figured this out on their own as well.
What seems odd though is Apple is giving the user the option to partially sync songs. It seems this differs from other services in that the local caching would occur while your iDevice is synching to your computer, caching the file from there, rather than downloading the information from the cloud. In an earlier patent Apple proposed a solution that would merge local and cloud based libraries into one. A problem arises for the operating system the device uses though. If cloud and local files are indiscernable and the experience must be the same, wouldn't the illusion be broken if a song is to be played, but needs moments to load? This partial synch could be the solution. The beginning of the song would be played, while a request for the rest of the song could be sent out from the device via the Internet.
It goes without saying this two year old patent (it was filed in 2009) by no means is an exact representation of the service Apple will ultimately implement. Still it seems odd that Apple could patent a method of local caching a year after Spotify started doing it. Not to mention the fact that most cloud-based music services operate this way.