Threshold Signatures and FROST: One Signature, No Single Signer (opens in new tab)

Splitting a key with Shamir's scheme protects a secret at rest, but to use it you have to reassemble the whole key in one place — and for one fatal moment, somebody holds all of it. Threshold signatures remove that moment entirely: a quorum jointly produces a valid signature while the complete private key never exists anywhere, not even briefly. FROST is the design that made this fast enough to deploy. Imagine three executives who must collectively authorize wire transfers, a custody service ...