Abstract:
Protecting SCADA and automation systems in the context of critical infrastructures against various cyber-attacks is a current challenge posed by their evolution towards Industry 4.0 and IIoT concepts. Since these systems either lack or employ insufficient security mechanisms within their comunication protocols and components, exposing their data to an outside network led to an increased number of cyber-attacks against them. This thesis focuses on designing and implementing security solutions for securing SCADA and automation systems considering timing constraints imposed by the industry while ensuring interoperability. The proposed security solutions are based on elliptic curve cryptography (ECC) and pairing-based cryptography (PBC) aiming to introduce or enhance the security of legacy communication protocols and OPC UA protocol, with focus on lower architetcural levels of SCADA and automation systems. In this context, several cryptographic authentication schemes based on HMAC, ECDSA and one encryption scheme based on ECIES for introducing security within legacy communication protocols are employed using in some cases trusted hardware devices (i.e., TPM, Optiga Trust X) and evaluated on lower-level constrained devices (i.e., PLCs). Moreover, for enhacing OPC UA security for client-server communication ECC-based and PBC-based methods are employed for ensuring data authenticty and integrity of the data vehiculated over the communication channel using ECDSA, BLS, BLS aggregated signatures. In addition, a tripartite DH scheme is implemented and evaluated for OPC UA communication. The security solutions presented in this thesis are evaluated on embedded devices and for several ECC-based solutions on PLC devices used in the industry in order to demonstrate the feasibility of integration within real industrial SCADA/automation systems.
