At 12:40 PM 8/27/2007, Curtis Preston wrote:
Every block coming into the device should be compared to every other block ever seen by the device.
As others have noted, different vendors dedup at different levels of granularity. When I spoke to Diligent at the Gartner conference over a year ago, they were very tight-lipped about their actual algorithm. The would, however, state that they were able to dedup parts of two files that had similar data, but were not identical. I.e., if data was inserted at the beginning of the file, some parts of the end of the file could still be deduped. Neat trick if it's true. Other vendors dedup at the file or block (or chunk) level. I've not been able to gather much more detail about the specific dedup algorithms, but hope to get some more info this fall, as take a closer look at these products. If anyone has more details, I'd love to hear them. ..Paul -- Paul Zarnowski Ph: 607-255-4757 Manager, Storage Services Fx: 607-255-8521 719 Rhodes Hall, Ithaca, NY 14853-3801 Em: [EMAIL PROTECTED]
