A Hybrid Pub/Sub and REST-Based Communication Strategy for Intelligent IoT System Interoperability

The Internet of Things (IoT) is increasingly deployed in critical infrastructure domains with stringent Quality of Service (QoS) requirements. The Web of Things (WoT) framework facilitates communication by enabling seamless interoperability between IoT systems and the broader Internet. However, WoT communication strategies often incur communication overhead and potential data loss, which may adversely affect QoS in IoT applications. Meanwhile, publish-subscribe systems are recognized for their lightweight, efficient, and reliable communication capabilities within IoT networks. To address the trade-off between robust intra-system communication and seamless inter-system interoperability, we propose a hybrid communication model that integrates publish-subscribe mechanisms for intra-system data exchange with REST-based protocols for inter-system communication. The architecture incorporates an AI/ML-capable Intelligent Web Gateway (IWG) to support hand-off between publish-subscribe and WoT communication. To validate the feasibility of the proposed architecture, we evaluate three commodity hardware platforms-NVIDIA Jetson Orin, Intel Next Unit of Computing (NUC), and Raspberry Pi 4-based on their ability to support expected workloads for IWGs. Our findings underscore the capability of off-the-shelf hardware platforms to support the proposed hybrid communication model and partially validate its practical deployment in IoT environments.