A hybrid key management method for robust SCADA systems and the session key generating method thereof

摘要

Disclosed is a hybrid key management method for a supervisory control and data acquisition (SCADA) system in which a master terminal unit (MTU), a plurality of sub-master terminal units (sub-MTUs), and a plurality of remote terminal units (RTUs) are sequentially and hierarchically structured, the hybrid key management method comprising the steps of: (a) creating, by the MTU and the sub-MTUs, their own secret numbers and making and exchanging digital signatures; (b) creating, by the MTU, group keys; and (c) distributing, by the MTU, the group keys to the sub-MTUs and encrypting and decrypting the group keys using the secret numbers.