IoT-NTN Communications via Store-and-Forward Core Network in Multi-LEO-Satellite Deployments

Since Rel-15, 3GPP has been working on adapting Low-Power Wide-Area (LPWA) radio access technologies, such as NB-IoT and LTE-M, to operate in Non-Terrestrial Networks (NTNs). More recently, a new Rel-19 study item named “Study on the integration of satellite components in the 5 G architecture, Phase 3” has been started to investigate how to integrate 5GS/EPS components into a satellite payload, how to address Store and Forward (S&F) satellite operation and how to enable UE-satelliteUE communications. This paper presents a novel solution addressing the S&F support, identified as Key Issue#2 in the 3GPP TR 23.700-29. The proposed mechanism introduces $S \& F$ satellite operations to support delay-tolerant services within multi-satellite IoT NTN deployments. Through this solution, the efficiency and reliability of communication networks in scenarios with intermittent connectivity are significantly enhanced, facilitating seamless operations of IoT applications across multiple satellites. The impact on services, entities and interfaces of the S&F-enabled core network is also investigated to identify necessary adaptations and new requirements for the terminals.