Authentication in an industrial control system

摘要

In a method for synchronizing user authentication data 22 in an industrial control system 26, the following steps are performed: calculating a first hash of the user authentication data 22 in a first controller 10a; broadcasting the first hash to a plurality of second controllers 10b in regular intervals; comparing the first hash with a second hash of user authentication data 22 in a second controller 10b; in the case, the first hash differs from the second hash, updating user authentication data 22 with an earlier timestamp with user authentication data with a later timestamp.