Public key-based quantum-resistant security scheme for IEEE C37.118.2 PMU communication

• Introduces FALCON-512 signatures for IEEE C37.118.2 PMU security. • Backwards-compatible design adds CFG-4 cert exchange and a signature field. • S-PMU-FALCON framework implements and validates the scheme in practice. • Delays stay within PMU real-time limits, even for large PDC-to-PDC frames. Phasor Measurement Units (PMUs) are critical devices in the smart grid that stream synchrophasor data to Phasor Data Concentrators (PDCs) and control centers in real time. The IEEE C37.118.2–2024 standard defines the protocol for PMU data transfer, but it lacks any built-in security mechanism. Integrity and authenticity are critical cybersecurity requirements to ensure reliable PMU data transmission. Existing security approaches in the literature rely on symmetric key-based authentication schemes, such as HMAC and GMAC, which require key distribution and management, posing scalability and security challenges. This paper proposes a public key-based security scheme employing quantum-secure FALCON Digital Signature Scheme (FDSS) into IEEE C37.118.2 synchrophasor communication. A custom software framework is developed to implement the FDSS-secured IEEE C37.118.2 messages to evaluate computational and communication overheads. Performance analysis demonstrates that FDSS meets real-time constraints even for large aggregated PDC-to-PDC frames, as it does not violate end-to-end delay limits for most PMU applications, making it feasible for IEEE C37.118.2 synchrophasor communication.