Securing the Realtime DER interface for the Netherlands: key takeaways from protecting IEC 61850 MMS with IEC 62351

The increasing numbers of distributed energy resources (DER) create capacity problems to the electricity system. In the Netherlands, System Operators (SOs) resort to congestion management for stability and safety. In 2020, SOs started the Realtime Interface (RTI) project, allowing SOs to monitor electrical measurements and send real-time operational setpoints to Customers, and enabling Customers to manage generation according to the capacity of the electricity system during a specific period. Cyber attackers might try to use the RTI to destabilize the electricity system by attacking SOs or multiple Customers. Therefore, the RTI was secured through a process that addressed the challenges of operations technology (OT), diverse systems and processes of SOs and Customers, and rapidly approaching project deadlines. This process engaged stakeholders in risk assessments, design meetings and a proof-of-concept (PoC). Security measures isolating RTIs from outside threats enable the rollout to start quickly. To prevent the increase of risk with the installed capacity, cryptographic protection of communication will be added, by using IEC 61850 MMS with TLS as described in IEC 62351. The PoC demonstrated that some Vendors already supported these measures, while other Vendors quickly and effectively added support to their products, although there were constraints to certificate management.