A Standardization Framework for Multi-Modal Underwater Wireless Communication to Enable the Internet of Underwater Things

This paper proposes a comprehensive standardization framework for Multi-Modal Underwater Wireless Communication (MM-UWC) to overcome the interoperability barriers hindering the development of a largescale Internet of Underwater Things (IoUT). The current underwater communication landscape is fragmented, dominated by non-interoperable, single-modal systems - primarily long-range, low-bandwidth acoustic and short-range, high-bandwidth optical technologies. This fragmentation impedes the complex, multi-stakeholder operations essential for the growing Blue Economy. To address this, we introduce a formal model for an MM-UWC system that intelligently selects the optimal physical medium based on real-time environmental data and application-level Quality of Service (QoS) requirements. Our standardization strategy is twofold: first, leverage the open NATO STANAG 4748 (JANUS) protocol as a universal 'handshake' mechanism for initial device discovery and capability negotiation; second, target the recreational diving industry, with its mature ISO standards ecosystem, as a strategic beachhead market for technology validation and adoption. Finally, we present a concrete roadmap for establishing a new series of international standards within the ISO/IEC JTC 1/SC 41 committee, which is ideally positioned to govern IoUT technologies. This framework provides a pragmatic path toward a robust, interoperable, and economically viable IoUT ecosystem.