SkyDrive in Windows 8.1: Cloud Storage the Way It’s Meant to Be
The files themselves use the reparse point mechanism first introduced in Windows 2000. During that first sync, stub files ("reparse points") are created to mimic the directory structure stored on SkyDrive. Any operation on these files is intercepted automatically, allowing SkyDrive to download the file on-demand.
The use of this (rather low-level) mechanism makes SkyDrive in Windows 8.1 very transparent. Virtually any application should work correctly, with only a download delay disclosing that a file isn’t stored locally.
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As a result, you can have tens or hundreds of gigabytes of files stored on a server, while still retaining pseudo-instant access. There’s no long sync process.
