vbuterin f5c5c166af Replace custody challenge game with JABS (#812) ... See also #818. === * Replace custody challenge game with JABS Replace the existing proof of custody game with a new game ("Justin's Awesome Bit Sum" or JABS) that works as follows: * The data `D` is split up into 512-byte chunks `D[0] .... D[n-1]`, and use a mix function `mix(subkey, data) -> {0,1}` (currently the first bit of the hash of `subkey+data`). We calculate `M[i] = (mix(D[0]) + ... + mix(D[i-1])) % 2`, and set the custody bit to `M[n-1]` * Anyone can challenge by providing the full `M` where `M[n-1]` is not equal to the custody bit * Anyone can respond to a challenge by providing a specific position in `M` along with a branch of the data where `M[i-1] ^ mix(D[i]) != M[i]` The maximum size of data is now `2**6` epochs * `2**6` blocks * `2**14` bytes = `2**26` bytes, so assuming 512-byte mix chunks the maximum mix size is `2**17` bits or `2**14` bytes. The average mix size is `2**8` bytes.		2019-03-28 22:56:43 +00:00
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0_beacon-chain.md	Merge pull request #848 from wmpea/patch-1	2019-03-28 13:16:01 -06:00
1_custody-game.md	Separate document for phase 1 custody game (#818)	2019-03-28 22:54:39 +00:00
1_shard-data-chains.md	Replace custody challenge game with JABS (#812)	2019-03-28 22:56:43 +00:00