3 ms·
Cutting a key in half doesn't halve its security, but it reduces it exponentially. 256 bits = 2^256 possibilities for bruteforcing 255 bits = 2^255 possibilit
by danuker 4y ago
Cutting a key in half doesn't halve its security, but it reduces it exponentially.
256 bits = 2^256 possibilities for bruteforcing
255 bits = 2^255 possibilities for bruteforcing, or half the security of 256 bits
128 bits = 2^128 possibilities, or 1/(2^128) the security
But you can have encryption schemes requiring N-of-M private keys to decrypt.
- chipsa 4y agoYou can cut a key in half without literally cutting it in half. Like: generate random 256bit number, xor with the key, and hand the random number to one party, and the xor'd value to the other party.