Hi Joachim,
I also tried my Google skills and used the wayback machine. But the wayback machine has only recorded http 300 errors. So my assumption is, that the link to this document is not correct.
My next attempt would be to contact Dale directly, if he still has a copy around. And, yes, I see he has already replied.
Dedup is an interesting idea, which can easily compress file system backups of client machines in TSM aka Spectrum Protect (at the moment), as they have many repeating patterns. I don't see much repeating patterns in database pages in a single database. Even without encryption or compression I assume the entropy of your data should be high enough to prevent duplicate pages.
It could be different for backing up many copies of the same database. However, then deduplication is probably blind to a single BACKUP command. Only in the backend, dedup can be resolved before saving to tape.
Just my €0.03 on the topic. And yes, I would also like to have a copy of the whitepaper. Just in case someone else is looking for this someday.
Cheers
Roland
P.S. Right after writing the above sentences, I re-read your OP again and I remember Dale saying, DEDUP_DEVICE is just a keyword to run a backup in a slightly different pattern to support external deduplication. But this also has implications to read from a stream. I have to think about this on my flight to IDUG NA next week...
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Roland Schock
IBM Champion and IBM Gold Consultant
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