The main outcome will be the availability of core technologies, architectures and protocols that can be indistinctly used for terrestrial or non-terrestrial networks for the provision of seamless services across an access and network fabric continuum overcoming the distinction between satellite and terrestrial access with seamless roaming capabilities between the two segments (beyond Hybrid network). It targets:

• Architectures and technologies requiring a very tight cooperation between the SNO and the MNO’s, towards a seamless TN-NTN communication continuum, and catering for a multiplicity of possible business models across the various domains.
• End to end service capabilities either through a TN segment or through an NTN segment, depending on relevant parameters including coverage, RT or NRT constraints, bandwidth and sustainability aspects.
• Innovative models such as managed multi tenancy of the space segment.
• Independent reconfiguration of the NTN part for performance, security and resilience optimisation.
• Compatibility with the most innovative use cases and their demanding requirements such as high rate Direct to Device, PPDR and other NTN specific use cases.
• Adaptability of the technologies, protocols and architecture (or a subset of those) to non-satellite scenarios such as drones or other flying 3D nodes.

The proposed Topic should cover R&I issues for low and medium TRL topics and plan, towards the end of the SNS implementation (i.e. later work programmes), for demonstration of critical technologies and applicability to specific use cases, e.g. with ESA partnership or national initiatives where possible, possibly using low-cost demonstrators such as Cubesat or equivalent EU offers.

Please refer to the "Specific Challenges and Objectives" section for Stream B-03 in the Work Programme, available under ‘Topic Conditions and Documents - Additional Documents’.

The scope of this topic focuses on the following areas:

• Management of multiple access networks through unified Control Plane capable of optimizing TN-NTN service provision according to traffic related parameters (QoS level, bandwidth, sustainability, latency, storage requirements...) and related RAN management, also accounting for very demanding use-case scenarios including public safety use-cases (e.g. PPDR) and system relying exclusively on satcom connectivity like aeronautic use cases.
• Management capabilities for independent reconfiguration of the NTN part for performance, security and resilience optimisation at system and subsystem level.
• Dynamic routing in multi-dimensional networks with selection of optimal paths for traffic, which is a key feature in leveraging the potential of NTN-TN unification and integration including optical links, improving (transport and mobility) protocols, flexible topology and traffic routing across such dynamic topologies with long-propagation link characteristics. For what concerns optical links (ISL) the approach is to consider them at system level characteristics and performance properties. However, development of specific technologies/subsystems for ISL is not in scope.
• Extension of a reference multi orbit constellation system(s) as evaluation framework for the assessment of routing and mobility schemes including various architectural splits. It should cover robustness of the scheme for disaster situation when TN is not available. The reference system may also address feasibility of the constellation considering spectrum usage from existing systems.
• Spectrum issues including i) novel schemes for dynamic spectrum access and sharing in FR3 (7 – 15 GHz possibly extended up to 24 GHz), providing good cost-coverage trade-off; ii) where applicable dynamic reuse of TN frequencies for NTN use where TN spectrum is not assigned or for very demanding scenarios including public safety use-cases.
• Multi tenancy and end to end resource slicing capabilities across multiple tenants, covering the space resources and including seamless mobility and handover between various segment, either TN to NTN or across 2 NTN infrastructures.
• Adaptability and versatility of the scheme to cover also non satellite 3D connected nodes and early system concepts (to be developed in subsequent phases) to provide GNSS free positioning with a better positioning accuracy/availability.

Notes: i) Specific satellite technologies such as advanced payloads and multi satellite generated antenna are not in scope from an in-depth R&I perspective. Their characteristics may be considered at system level where appropriate, but their detailed development is not part of the SNS JU WP objectives, ii) satellite architectures with different levels of data processing (e.g. transparent or regenerative space segments) are in scope.

Applicants should clearly identify the areas/priorities they address in case they only cover a subset.