5 ms·

It would be interesting to know more about how to make mining dependent on space and not cpu. Seems like you could use cpu to compress and create more space, th

• sigil 9y ago
  There is such a thing as a Memory Hard Function (MHF). cperciva's scrypt was designed to be one, and was subsequently proven to be maximally memory hard. https://eprint.iacr.org/2016/989.pdf https://eprint.iacr.org/2016/989.pdf Litecoin uses scrypt.
  • cperciva 9y ago
    Litecoin doesn't use scrypt. It uses a nerfed variant of scrypt which is not memory hard.
    • sigil 9y ago
      Thanks for the correction. I have no idea why they would do that, do you? Isn't memory hardness the entire point?
• kpcyrd 9y ago
  You can only compress to a certain level. For example, you can't compress a sufficiently random bitstream because there are no patterns. See also information theory. I wrote a game for programmers about 5 years ago that used a toy proof-of-storage system. It gave as many 1GB blobs to players as requested, picked random chunks and stored checksums of those. The player doesn't know which chunks have been picked. Some hours later you could start the challenge that you still have the file and the system challenged you to send the checksum of the chunks it picked. If you could answer this, you obviously still have the file and got points. This allowed the system to force a player to store 1GB of data while the verification only needed some bytes of storage.