De-duplicated files vs. Single Instance Storage (SIS)

[sapidus]

I've heard it said that SIS and dedupe are NOT the same.  But I don't understand the points of difference.  I thought if I went through all the files, and removed the duplicates, and stored only a "single instance" of that file, then I had created a single instance through the process of deduplication.

What else is there?

[TonySterling · Accepted solution]

This might be a bit tough without a whiteboard.  ;)

Think of it like this, an email comes in with an attachment and goes to two people, archiving occurs and Single Instance kicks in so there is only one copy.  Now, someone replies to that email and adds some text in the attachment.  De-duplication kicks in and only stores the newly added text. 

That is very high level and actual levels of de-dupliction will vary by rules etc... but I hope that helps. 

Message Edited by Tony Sterling on 09-30-2008 01:28 PM