Patent attributes
Methods and apparatus are provided for proactivized threshold password-based secret sharing with key rotation. An exemplary method comprises determining a difference between updated and prior values of a share, wherein the updated value comprises a fixed share of a plurality of shares of a secret; setting at least one polynomial coefficient of a correction polynomial employed by a polynomial-based secret sharing scheme to a value that depends on the difference; applying the polynomial-based secret sharing scheme to obtain share correction values that comprise a share correction value for the fixed share derived from the at least one polynomial coefficient; and providing the share correction values to at least one party that generates the fixed share from the provided share correction value for the fixed share and the prior value of the share. The secret can optionally be updated. A key rotation scheduler optionally performs a new sharing of the secret based on a refreshing schedule and/or a refreshing policy.
