The other posters are correct.  You will get 1:1.   Dedupe works by
finding patterns.  There are no patterns in encrypted data.

One question would be why would you do that?  Most people are encrypting
data as it leaves their site.  The best way to do that is hardware
encryption (tape drive or SAN-based).  Do that on the other side of your
dedupe box and before it goes to tape -- not at the client -- and you'll
have no issues with dedupe.

---
W. Curtis Preston
Backup Blog @ www.backupcentral.com
VP Data Protection, GlassHouse Technologies 

-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf Of
lamont
Sent: Wednesday, January 23, 2008 12:29 AM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: [ADSM-L] Data Deduplication

Hi,
What would likely be the de-dupe ratio if tsm clients do archive
processing daily (file level, no tdps) with encryption enabled?

Thanks.

+----------------------------------------------------------------------
|This was sent by alancb AT gmail DOT com via Backup Central.
|Forward SPAM to abuse AT backupcentral DOT com.
+----------------------------------------------------------------------