DeltaCopy is rsync for Windows. It’s open source and is available for NT4, 2000, XP and 2003. The idea of rsync is that if you’re trying to backup files on a regular basis, then a normal backup program would copy everything during every time interval. This is a waste of bandwidth. But if you only copy what has changed, then it’s more efficient use of the bandwidth. DeltaCopy accomplishes this by basically wrapping the rsync program with a Windows wrapper program.
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