Runtime integrity assurance and self-healing recovery for roadside edge infrastructure in connected transportation

Roadside edge infrastructure is becoming an active execution layer in connected transportation. Roadside units, edge servers, and vehicular gateways not only relay safety messages, but also run local services and support traffic-control decisions. Once these nodes are compromised, data authentication, blockchain logging, or forensic evidence management cannot by itself guarantee service trustworthiness, because the node that senses, signs, forwards, or processes the information may already be running an unauthorized software stack. This paper presents RISE-CT, a runtime-integrity assurance and self-healing recovery framework for roadside edge infrastructure. RISE-CT models each node through a layered security-state graph covering hardware roots, boot chains, firmware images, runtime processes, key usage, and service status. It combines boot-time, periodic, and event-triggered attestation with runtime drift diagnosis to detect firmware deviation, process injection, abnormal key access, replayed evidence, and service-behavior changes. When the risk score exceeds policy thresholds, a risk-aware admission state machine moves the affected node into degraded, quarantined, or recovering states, and coordinates service migration, key renewal, firmware rollback, and re-attestation before safe re-admission. Seed-controlled emulation under firmware tampering, malicious OTA updates, runtime injection, key misuse, replayed attestation, and roadside-service hijacking shows that, under the evaluated emulation settings, RISE-CT reduces the representative detection delay to 0.98 s and service interruption to 0.82 s, while achieving a 0.94 re-admission success rate with controlled attestation overhead. The results suggest that runtime node integrity can provide a potential security mechanism for improving the trustworthiness of roadside infrastructure under the evaluated conditions.