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Member "lessfs-1.7.0/COLLISION.probability" (30 Sep 2011, 527 Bytes) of package /linux/misc/old/lessfs-1.7.0.tar.gz:


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    1 The tiger hash that is used is 192 bits long.
    2 No known hash collisions exist as far as I know for the full hash.
    3 
    4 2^192 = 6277101735386680763835789423207666416102355444464034512896
    5 Lets say that we want to store 1024 PB of data.
    6 1024PB = 10^18
    7 10^18 = 1000000000000000000
    8 
    9 The chance that the the hash collides with a 4k blocksize is:
   10 1000000000000000000/4096 = 244140625000000 blocks
   11 This is : 1:25711008708143844408671393477458
   12 
   13 Compare the number above with the risk of dying in an airplane crash : 1 in 10 million at best.