I. INTRODUCTION  
A. Background  
B. Prior Related Surveys  
C. Scope and Contributions  
D. Structure and Organization  

II. NGSO SYSTEM CHARACTERISTICS AND CLASSIFICATION  
A. Space-based Internet Providers  
B. NGSO Space Missions  

III. NGSO COMMUNICATION PROSPECTS  
A. Physical and Radio Access Aspects  
B. Networking Aspects  
C. System and Architectural Aspects  

IV. NGSO DEPLOYMENT CHALLENGES  
B. Satellite Constellation Design  
C. User Equipment  
D. Operational Issues  

V. FUTURE RESEARCH DIRECTIONS AND OPPORTUNITIES  
A. Open RAN  
B. Broadband Connectivity for Space Missions  
C. Edge Computing  
D. Space-based Cloud  
E. IoT via NGSO Satellites  
F. Caching Over NGSO Satellites  
G. Aerial Platforms and NGSO Coordination  

VI. CONCLUSIONS