# SatEC: A 5G Satellite Edge Computing Framework Based on Microservice Architecture
## 1 Introduction  
Fifth-generation (5G) Next Generation Communication Networks will be a global game changer from technological, economic, societal, and environmental perspectives [1]. In the future, 5G networks will be mainly used to meet the needs of enhanced mobile broadband services of approximately two billion users worldwide, as well as providing high reliability and low latency services in key communication scenarios [2]. The requirements of 5G networks for global coverage and low latency will have a great impact on the existing mobile network architecture of mobile operators.  
The IMT-2020 (5G) Promotion Group defines \"seamless wide-area coverage\" as one of the four technical scenarios of 5G networks [3]. Terrestrial 5G communication requires ground base station support. Limited by economic costs, technology, and other factors, ground base stations cover only ~20% of the total land area. In desert, polar, and ocean regions, and other geographical locations where it is difficult to build the base stations, there are no communication networks. The wide-area coverage of a satellite radio access network could solve the coverage problem in 5G networks [4; 5; 6; 7; 8]. In recent years, advances in radar and laser communication technologies have made satellite communicationsmore bandwidth, less cost, and lower latency [9]. O3b [10], OneWeb, SpaceX Starlink [11], and other low-orbit satellite constellations combine satellite communication services with Internet services, making it easier for users to connect to satellite networks.  
However, in the development of traditional satellite communication, there is no unified framework and service interface, resource utilization is low, and computing power is poor. To provide services, satellites need to access ground computing centers to transmit data, which takes up a large amount of bandwidth and causes a high delay. In order to solve the delay problems, the ground 5G network uses Mobile Edge Computing (MEC) to place part of the computing resources at the edge of the network, which can effectively save bandwidth and reduce delay [12; 13; 14; 15; 16]. Considering the low latency requirements of 5G networks and the limited bandwidth resources of satellite networks, in this paper we propose a 5G Satellite edge computing framework (5 GsatEC). In terrestrial 5G communication, edge computing already exists, but the concept of edge computing on satellites is rarely mentioned. In the past, the resources of computing, storage, and network in satellites were all developed for specific applications, rather than the universal edge computing that supports multiple applications.  
There are three main contributions of our work. This paper presents the system framework of the 5 GsatEC and its resource platform. The hardware of 5 GsatEC is based on an embedded platform, and the software is decomposed into microservices. By using an embedded platform, 5 GsatEC provides resources with low power consumption. Moreover, the platform has a wide variety of resources, and the optimal resource combination can be used to realize different services. Microservices will shield the underlying interface and provide available resources in the form of basic services [17; 18]. Finally, the system characteristics of the ground network, satellite network, and 5 GsatEC are simulated by MATLAB, which proves that the SatEC framework is highly feasible and can effectively guide the construction of practical applications.  
This paper is organized as follows. Section 2 introduces the related research regarding satellite communication with 5G and satellite on-board computing. Section 3 introduces the SatEC system framework structure in terms of hardware and software. Section 4 reflects the system characteristics through a typical service for SatEC on the 5G satellite. Finally, Section 5 presents a conclusion based on the advantages and limitations of the SatEC system and offers a suggestion for future research.