I must be missing something here. Can't you just use a one-time-pad to encrypt your seed phrase? OTP is unbreakable without the pad phrase and anyone can implement it using no more entropy than a coin to flip. I get that the k out of n shares thing could useful in some situations ...
I am not super familiar with OTP but from what I can gather it would work as well. There's an app that can perform this calculation here: www.boxentriq.com/code-breaking/one-time-pad. The unique thing about shamir is that the seed is broken up into parts that can be geographically distributed. OTP just appears to give you a string like this: KBPSVRWQOEIEFOUXVYOLZMDEMVMPEEOCWYJEINOSUXSQVPSQFZHOTVVVKEDLCJ. Very different but potentially very useful. Thanks for the tip!
@SVRNMoney I don't think you need an app. Flip a coin - heads you consume a character of your seed phrase, tails you consume one of your pad phrase. If the characters are the same, consume the pad phrase. If you have enough flips in a row to reveal a significant phoneme, turn the coin over. Continue until you've consumed the whole pad phrase. That way anyone who knows the pad phrase can just cross out every character from it - a child could do it - to reveal the seed phrase. But since the ciphertext has exactly the same statistics as English, and since the combinatorics are so big, no one without the pad phrase can crack the result. Not without a quantum computer big enough to crack bitcoin itself, anyway. I don't know what the name of this OTP method is, but it's so.simple it must have one. Since I'm not a cryptographer I make no claims about its strength ...
I must be missing something here. Can't you just use a one-time-pad to encrypt your seed phrase? OTP is unbreakable without the pad phrase and anyone can implement it using no more entropy than a coin to flip. I get that the k out of n shares thing could useful in some situations ...
I am not super familiar with OTP but from what I can gather it would work as well. There's an app that can perform this calculation here: www.boxentriq.com/code-breaking/one-time-pad. The unique thing about shamir is that the seed is broken up into parts that can be geographically distributed. OTP just appears to give you a string like this: KBPSVRWQOEIEFOUXVYOLZMDEMVMPEEOCWYJEINOSUXSQVPSQFZHOTVVVKEDLCJ. Very different but potentially very useful. Thanks for the tip!
@SVRNMoney I don't think you need an app. Flip a coin - heads you consume a character of your seed phrase, tails you consume one of your pad phrase. If the characters are the same, consume the pad phrase. If you have enough flips in a row to reveal a significant phoneme, turn the coin over. Continue until you've consumed the whole pad phrase.
That way anyone who knows the pad phrase can just cross out every character from it - a child could do it - to reveal the seed phrase. But since the ciphertext has exactly the same statistics as English, and since the combinatorics are so big, no one without the pad phrase can crack the result. Not without a quantum computer big enough to crack bitcoin itself, anyway.
I don't know what the name of this OTP method is, but it's so.simple it must have one. Since I'm not a cryptographer I make no claims about its strength ...