Patent ID: 9130757
Filing Date: 2015-09-08
Classification: H04L

Abstract:
1. A method comprising: distributing shares of a private signature key to a group of users with a first processor; producing a plurality of sub-shares from each of said distributed shares with a processor associated with at least one user of the group of users, with each sub-share being accompanied by a corresponding validity proof; distributing the plurality of sub-shares among a set of new users, wherein each of the group of users receives sub-shares from a multiple users; verifying whether each sub-share in that is received by the each user of the set of new users is valid; and combining said valid sub-shares from multiple existing users at each one of the set of new users to generate a set of new shares, each said new share being derived from valid sub-shares from multiple users, wherein, based on said verifying determining that a received sub-share is invalid, said invalid sub-share is not used in said generating.