How does De-duplication compare to delta technology. If only a portion of a file (10MB of a 1GB file) is updated, how will de-duplication work?
Yes, if you update only a portion (say 10MB of a 1 GB file), only the changed portion gets backed up the next time. In this way its similar to delta technology. De-duplication is much more advanced than delta-technology and much more. Delta technology is useful for a single file that is being modified – de-duplication includes delta technology and performs the same type of delta backup. De-duplication can detect common portions across files. So lets say you have two files on a computer that are identical, de-duplication is able to detect it and store only one copy. In addition, if the two files are not identical, but have some common parts (like would be the case with multiple versions/copies of a database or word document), de-duplication will detect commonality across files and store the common portions only once. De-duplication has been shown to often help reduce storage by 20 times to 40 times.
