ReverseDelta™ is technology developed by Altaro Software, that enables BackupFS and Oops!Backup to only save the changes between each version of a altered file, rather than backing up the whole file every time it changes.
This means that keeping multiple backup versions will require less space on your backup drive.
What distinguishes ReverseDelta™ from other delta technologies?
Many users are apprehensive if this version may need to be rebuilt from an older version and one or more delta files.
With ReverseDelta™, the latest version of a file is always made available in its entirety and not as a delta file. This means that if you require the latest version of a file, it is possible to access it directly from your backup drive without having to rebuild it from delta files. The delta files are only used if you want to build a previous version of the file, building one delta file at a time for each version as you travel back in time in the reverse direction.
ReverseDelta™ is recommended for large files that change often, such as Outlook PST files or database backup files.
The downloadable diagram below shows a more visual representation of the whole process. The diagram represents a simple example of a file that is backed up four times (the first time, followed by 3 different versions of the file), and conveys the way ReverseDelta™ optimizes the storage space on the drive.
Steps 1,2 and 3 show the initial stages involved in transferring a file to the backup with ReverseDelta™, followed by Step 4, which may be repeated indefinitely. Step 5 shows how older backups can be deleted, and Step 6 shows how a particular version of the file is restored from the delta files.
