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"ZKCP is a transaction protocol that allows a buyer to purchase information from a seller using Bitcoin in a manner which is private, scalable, secure, and whic
by dkopi 11y ago
"ZKCP is a transaction protocol that allows a buyer to purchase information from a seller using Bitcoin in a manner which is private, scalable, secure, and which doesn’t require trusting anyone: the expected information is transferred if and only if the payment is made. The buyer and seller do not need to trust each other or depend on arbitration by a third party."
One obvious, and sad use for this is Cryptolockers.
I prove that I have the key to decrypt your files, you prove that you have the BTC to pay for it.
- hyperbovine 11y agoBut there will be many more non-obvious, non-sad uses for it.
- ycmbntrthrwaway 11y agoAnd as usual with crypto technology, "bad guys" already have means to achieve their goals anyway. Cryptolockers already exist.
- hnmcs 11y ago> scalable But not scalable beyond BitCoin's ~7 transactions per second, right? Asking because I read this last month: http://www.nytimes.com/2016/01/17/business/dealbook/the-bitcoin-believer-who-gave-up.html http://www.nytimes.com/2016/01/17/business/dealbook/the-bitc...
- nickodell 11y agoNo, not scalable beyond that.
- flatline 11y ago~2.7 tps in practice, and shrinking as transaction sizes grow.
- ikeboy 11y agoThese transactions work fine with the lightning network, according to the author on reddit: https://www.reddit.com/r/Bitcoin/comments/47rk85/first_successful_zeroknowledge_contingent_payment/d0fbysd?context=3 https://www.reddit.com/r/Bitcoin/comments/47rk85/first_succe... So this can scale as much as lightning can. See https://en.bitcoin.it/wiki/Scalability_FAQ#Doesn.E2.80.99t_Lightning_require_bigger_blocks_anyway.3F https://en.bitcoin.it/wiki/Scalability_FAQ#Doesn.E2.80.99t_L... and https://blockstream.com/2015/09/01/lightning-network/ https://blockstream.com/2015/09/01/lightning-network/
- ewillbefull 11y agoAdditionally, lightning actually uses the HTLC (Hashed Timelock Contract) transaction style that is used by ZKCPs. I believe it is used to extend lightning channels to multiple hops.
- ryan-c 11y agoI'm not sure this is actually useful to cryptolockers. They could use it to sell the private key to a particular public key, but I don't think they can prove that * That public key was used to encrypt the files * Even if they can prove that, prove that the files (aside from maybe one or two samples) will decrypt to the originals.
- joosters 11y agoCryptolockers already provide a very simple proof to their 'customers': they offer to decrypt one file of the victim's choice, for free.