Potent: energy-optimized and cache-enhanced routing for high-performance terrestrial–aerial networks

High-altitude platform systems (HAPS) have recently attracted significant attention due to their unique characteristics and wide range of potential applications. In particular, cloud-based HAPS (C-HAPS) provides a framework for deploying and delivering cloud services directly from HAPS station data centers. In our previous work, we introduced a C-HAPS-based architecture for environmental and infrastructure monitoring that integrates a wireless sensor network (WSN) with a blockchain model. In this paper, we propose a novel energy-aware and cache-enhanced routing protocol tailored for C-HAPS. The proposed approach addresses the resource constraints of sensor nodes that relay data to the HAPS data center by jointly considering residual energy and geographical location as the primary metrics for routing decisions. Furthermore, we introduce a data caching mechanism based on the concepts of cache data and cache location to further improve network performance and efficiency. Simulation results demonstrate that the proposed protocol outperforms existing terrestrial–aerial routing schemes in terms of packet delivery ratio, data request delay, energy consumption, and cache hit ratio, confirming its effectiveness and robustness for next-generation HAPS-based IoT environments.