Ocarina Networks, or Ocarina as they are usually called are a company that specialize in a thing called data deduplication and compression. Basically you can think of it as removing all the data that you find more than once and replacing all duplicates with a pointer to just one original version of the data. This can be done on multiple levels, and the most 'simple' version would be to use a corporate mailbox as an example. Say you would send out a mail to 5 colleagues with a Powerpoint presentation you want them to review. Normally each recipient will have a copy of this file in his or her mailbox and consume the space for the attached file. A deduplication solution could for example look and find that the same file exists 5 times. It saves one version and has the others just point to this one file.

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