Improved robust distributed key generation

Abstract

A method for distributed generation of private key shares for a plurality of cryptographic devices is disclosed, allowing a number of cryptographic devices to be corrupt. The method may use a preprocessing phase that includes sharing symmetric keys among subsets of cryptographic devices. The subsets derive a private key from the symmetric key and broadcast a hash of a corresponding public key. A subset is excluded if some device fails to broadcast the correct hash. A private key share may now be derived from the private keys for non-excluded subsets.

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