# A Review of SATis5: Perspectives on Commercial and Defense 5G SATCOM Integration
## 6 Outlook Perspectives on SATis5 for Commercial and Defense Applications
### Defense SATis5 Applications  
The survey results captured in Section 5 indicate that the Aerospace defense industry is currently focusing on the development of SATis5 architectures that can address multi-domain defense operations. This domain includes but is not limited to (i) Integration of defense satellites with a 5G tactical gateway that enables JADC2 across all battlefield assets, (ii) Satellite-enabled 5G wireless network supporting operations and flight traffic management, (iii) Deploy secure 5G nodes at the tactical edge, and (iv) Integration of the GNSS with 5G networks enabling global positioning, navigation, and timing (PNT) capabilities. In general, defense satellites represent a wide range of space-based systems, including military SATCOM satellites (e.g., US Wideband Global Satellite System), defense sensing  
Figure 14: Top-level SATi5 architecture perspective for commercial applications. satellites (e.g., US Space Based Infrared System), and PNT satellites (e.g., US Global Positioning System). To achieve seamless multidomain defense operations enabling JADC2 across all battlefield assets, a unified enterprise SATis5 architecture requires integrating all existing defense satellites with 5G networks. This integration poses potential technical and programmatic challenges, including hardware/software interoperability, capabilities synchronization and alignment, and cost/schedule synchronization. This section provides our outlooks on potential SATis5 architectures for integrating existing and future MILSATCOM satellites with 5G networks. The outlook for a defense SATis5 architecture that we envision is like Figure 14 with the commercial satellite being replaced by MILSATCOM satellites. Since MILSATCOM satellites employ TRANSEC mechanisms at PHY/Datalink/MAC layers, the commercial defense SATis5 architecture components are required to modify to address the TRANSEC mechanisms:  
* MILSATCOM Satellite Payload: The payload's air interface should be modified to adapt to the 5G network's components, including NTN-LT-gNB, NTN-NT-UE, 5G-UEs, and 5G-NGC;
* CSP RAN (VNF): This CSP RAN can be replaced by a \"Dedicated RAN\" that allows the satellite gateway to process and manage the TRANSEC mechanisms associated with PHY/Datalink/MAC layers. The dedicated RAN will allow the satellite access to data networks through the 5G-NGC core network or mobile network operator core network. The NTN network termination gNB (NTN NT gNB) located at the satellite gateway should also be modified to (i) perform TRANSEC processing and management, and (ii) transport encapsulated control plane (CP) of the gNB;
* NTN Terminal: The Satellite CPE for the NTN Terminal can be replaced by \"Dedicated NTN Terminal\". The NTN Terminal should be modified to adapt to PHY/Datalink/MAC layers associated with TRANSEC mechanisms;
* 5G UEs and MILSATCOM Satellite User Terminals: The users' equipment and terminals should also be modified to adapt to the PHY/Datalink/MAC TRANSEC mechanisms associated with MILSATCOM satellites; and
* 5G-NGC: This should also be modified to manage the integrated SATis5 network resources effectively. The modified 5G-NGC is responsible for managing the use of communication resources optimally for both MILSATCOM and 5G networks. In addition to the above modifications, other layers are also recommended for further investigation. For example, a mission optimizing orchestration layer, which is at Layer 8 or Layer 9 beyond the Application Layer of the standard OSI stack, will be needed for various JADC2 use cases for defense applications. Note that this orchestration layer provides \"state-of-play\" functions that can be supported by (i) 5G Mobile Edge Computing of Layer 0 and Layer 1, and (ii) Layer 2 and Layer 6 of cyber electronic warfare multi-access Edge Computing (EW MEC). The bottom-up approach for big data to build the state-of-play is based on the user plane function, unified data function, and policy control function of 5G technologies.