Shamir's Secret Sharing Scheme - what fun!
The links to
Secret sharing (also called secret splitting) refers to methods for distributing a secret amongst a group of participants, each of whom is allocated a share of the secret. The secret can be reconstructed only when a sufficient number, of possibly different types, of shares are combined together; individual shares are of no use on their own.
In one type of secret sharing scheme there is one dealer and n players. The dealer gives a share of the secret to the players, but only when specific conditions are fulfilled will the players be able to reconstruct the secret from their shares. The dealer accomplishes this by giving each player a share in such a way that any group of t (for threshold) or more players can together reconstruct the secret but no group of fewer than t players can. Such a system is called a (t, n)-threshold scheme (sometimes it is written as an (n, t)-threshold scheme).
Secret sharing was invented independently by Adi Shamir and George Blakley in 1979.
Good reasons to use this:
- good passwords are hard to remember - split it and then put in multiple places or give it to multiple friends, so if you forget, then you can get it back
- a "dealer" could send multiple parts through different methods (i.e. email, IM, etc.) and an attacker would have to intercept all of them to be able to get the code
- something where if a primary person wasn't available, but enough of the secondary people were and agreed it was important enough, then the secret could be revealed
Seems pretty cool.
Can install it on MacOS by using brew and brew install ssss.