Topological Modeling and Routing Protocol for In-Vivo Nanosensor Network

In-vivo Wireless NanoSensor Networks (iWNSNs) have emerged as a promising paradigm for real-time biomedical monitoring, supported by nanosensors capable of detecting biochemical markers at extremely low concentrations. Among various possible application scenarios, gastrointestinal environments represent an important but challenging domain for in-vivo communication. Motivated by these application needs, this paper develops a topological model derived from the static morphology of the stomach and proposes a Multi-hop Energy-Balanced Clustering Routing protocol, termed MEBCR, for THz-based iWNSNs. MEBCR employs an unequal-clustering strategy to optimize cluster-head selection and competition radius while dynamically adjusting cluster sizes to mitigate uneven energy consumption. Simulation results show that MEBCR significantly enhances energy balance, prolongs network lifetime, increases data-delivery reliability, and reduces end-to-end delay. These results illustrate that the proposed approach can effectively support THz-band in-vivo nanosensor applications, with gastric monitoring being one representative use case.