Patent ID: 11671255

Abstract:
A method of sharing a secret value is disclosed. The method comprises distributing respective first shares of a first secret value, known to a first participant (Pi), to a plurality of second participants (Pj≠i), wherein said first shares are encrypted by means of at least one private-public key pair comprising a private key and a public key being an elliptic curve generator point multiplied by the private key and wherein a first threshold number of first shares is required in order to enable a second participant to determine the first secret value. At least one second share of a respective second secret value is received from each of a plurality of second participants, wherein the second shares are encrypted by means of at least one private-public key pair comprising a private key and a public key being an elliptic curve generator point multiplied by the private key, and a second threshold number of second shares is required in order to enable a participant other than that second participant to determine the second secret value. A third share of a third secret value is formed from a plurality of second shares, wherein a third threshold number of third shares is required in order to enable the third secret value to be determined.