Recent research in vehicle-to-infrastructure (V2I) communications within Vehicular Ad Hoc Networks (VANETs) focuses on enhancing connectivity and intelligence between moving vehicles and fixed roadside infrastructure to support modern intelligent transportation systems (ITS). Studies are increasingly exploring dynamic roadside unit (RSU) placement strategies, edge/fog computing–enhanced RSUs, and adaptive communication protocols that respond to real-time vehicular density, speed, and network load. Hybrid wireless technologies (such as DSRC, C-V2X, and reconfigurable intelligent surfaces) are being integrated to extend coverage and increase reliability in high-mobility environments. Concurrently, machine learning models are being deployed at the infrastructure level to manage spectrum allocation, predict traffic flow, and enable ultra-low-latency interactions for safety, navigation, and infotainment services. Security and privacy concerns are also being addressed through lightweight cryptographic schemes and trust frameworks tailored for V2I links. Together, these advances are paving the way for smarter, more resilient, and data-driven V2I communication layers that underpin the future of connected and automated mobility.