A company called Ocarina Networks says they "make free space on storage you already have" through some very clever content aware compression and de-duplication. The key element here is that it works on your online storage so the savings are multiplied as there are flow on effect to the transmission of your data over networks and to the amount of data that you need to backup. So even though companies like Netapp (which Ocarina say they are 57x better than) and DataDomain do de-dupe its only at the underlying storage without these possible secondary benefits.

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