Comment by teravor

16 hours ago

if the secret is large usually it's encrypted and the payload is distributed along with the shares of the key.

but you can also just use Reed-Solomon and split the payload, the difference with Shamir is that you lose information-theoretic security (you lose it the moment you use encryption anyway) and the payload also needs to undergo an all-or-nothing-transform (AONT).

AONT transforms the entire payload into an encrypted blob which also serves as its own key, a withheld piece is a de facto encryption key. this is required because Reed-Solomon can have pathological cases where pieces leak information.

Reed-Solomon is an Erasure code, and I definitely wouldn't look to that for Secret Splitting. Those leakage models are gnarly. But if you want something else that is more general - there are Monotone Span Programs. Seriously underused.

  •     > Reed-Solomon is an Erasure code
    

    which shares the same math as Shamir

        > Those leakage models are gnarly.
    

    AONT solves that by making any leak other than the totality meaningless