Discreet Log Contracts settled with Chaumian ECashconduition.io/cryptography/ecash-dlc/
4663 sats \ 9 comments \ @conduition 19 May bitcoin
Today I’d like to describe a way to use Chaumian Ecash to commit to a conditional payment using an Ecash mint as a blind but trusted intermediary.
Technical feedback appreciated - Comment on my PR here
Do you think this would make a good NUT on the Cashu spec?
What would you build if you had access to a DLC-enabled Ecash mint?
write
preview
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124 sats \ 2 replies \ @conduition OP 19 May
@calle Would love your opinion on this if you have a moment
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104 sats \ 0 replies \ @south_korea_ln 20 May
@calle pops in here once in a while, but I guess you'll have more luck pinging him on NOSTR and telling him you posted here if you want to have quick feedback...
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250 sats \ 0 replies \ @calle 25 May
I love this and I'm happy to say that we have almost everything you need to build this.
NUT-10 specifies what scripts in general should look like: https://github.com/cashubtc/nuts/blob/main/10.md
NUT-11 is an example of a script. You can probably copy most of it (of the code) and replace relevant parts with your DLC ECC operations instead of the schnorr signature check. That's the easiest I can think of, maybe there are better approaches.
definitely join our discord though: https://discord.gg/rTGxfneh
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10 sats \ 0 replies \ @grayruby 19 May
I don’t understand the technical aspect of this at all but the concept sounds promising.
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121 sats \ 1 reply \ @BlokchainB 19 May
Who wants a nut?
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0 sats \ 0 replies \ @Car 20 May
Lol
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0 sats \ 1 reply \ @025738dda8 25 May
I like your articles, thanks! I am trying to understand the first part now - Ecash.
I am missing at least one feature that puzzles me. The Z = Q - rM. How can anybody proof that the Q (or Z) comes from the Mint? Also, I am missing the undeniability that this token comes from the particular Mint. Is this a part of the trust layer here?
(When briefly skimming over the paper Blind signatures for untracable payments from D. Chaum, I found the property "anybody can check that signature was formed using signer's private key".)
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5 sats \ 0 replies \ @conduition OP 28 May
Disclaimer: I haven't actually read Chaum's original paper yet. My knowledge is derived from reading the cashu specs (called 'NUTs'). So I can't speak to Chaum's original design.
In Cashu though, the proof Z is not verifiable by anyone but the mint itself. In order to prove a token was indeed issued by the mint, either:
  • the recipient of Z must ask the mint to swap the ecash out, thus verifying its authenticity in the process
  • the mint must supply some extra information to allow offline verification of Z. See NUT-12 for that.
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0 sats \ 0 replies \ @Fabs 20 May
Man man man, ain't you a hardworking 🐝 !
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