Difference Between Incremental and BitBackup
The bottom line: Use Incremental for almost everything. Use BitBackup for very large files that change only a little, like CAD drawings.
Incremental backup will scan for files' archive flags and backup the files which have been changed since last backup. The operating system automatically sets the Archive Flag on each file that is edited. Incremental always backs up full files. That is why incremental backup is recommended for small size files.
Bitbackup on the other hand will backup only changes. Here is an example.
Lets say there is a 1 GB file. If you backup this file using the Incremental backup type, the first backup will be a FULL backup and then if this file is ever changed (for example, 100MB is added, so now the size is 1.1 GB), the next incremental backup will backup this 1.1 GB file.
If you backup this file using BitBackup, the first backup will be a FULL backup and the next backup only the 100 MB that has been added.
So, BitBackup will not do a backup of entire 1.1 GB. This is the reason BitBackup is recommended for very large files that change only a little - like CAD drawings.
The BitBackup process takes more time than Incremental backup because it has to scan entire files and extract changes while comparing previous versions. It is NOT a good idea to use BitBackup for all files because of the slower speed and because it requires sometimes a lot of temporary space on the Endpoint computer.
Do not use BitBackup on medical radiographs, movies, pictures, sound files, or other large files that NEVER change.
The Endpoint-side disk space needed for Incremental is only temporary, just enough to store the backup files that have been prepared for backup but not sent to the Server yet. The files are deleted from the local drive after they have been verified on the Server. The number of files queued up locally is 100 by default. This can be adjusted, and the location of the temporary file path can also be set to another drive if needed.
BitBackup uses permanent space on the Endpoint to store its reference files. This is called the BitBackup Ref Path. It needs about one and a half times the size of all the files included in a BitBackup backup set. Because this can be such a large amount of space, we recommend against using BitBackup except on specific file sets containing large files that change just a little.