## 1 Introduction  
Nowadays, there are thousands or even tens of thousands of satellites in Low Earth Orbit (LEO) [1, 2]. LEO satellites operate at altitudes of 160 to 2000 km [3], and a large number of LEO satellites can form a constellation of an LEO satellite network, providing global coverage services for terrestrial users [4, 5]. Some people suggest using it as a key infrastructure for the upcoming 6G network and beyond [6, 7, 8, 9]. However, the cost of constructing an LEO satellite constellation is enormous. The cost of an LEO satellite is approximately USD 65,000; although it is nearly 10,000 times lower than the cost of a costly \"exquisite\" satellite (e.g., $650,000,000) [10], LEO satellite constellations based on a large number of LEO satellites still face huge economic costs. For example, one of the state-of-the-art LEO satellite networks, SpaceX's Starlink, has over 2000 satellites in different LEO groups currently. Furthermore, the Federal Communications Commission (FCC) has approved Starlink to bring that number up to 12,000 [4]. Moreover, there are many competitors in the industry for LEO satellite constellation construction; OneWeb and O3b are another two leading enterprises in this industry [11, 12]. Intense competition drives companies to create better satellite products, which will inevitably exacerbate the already significant economic pressure.To ensure the economic sustainability of LEO satellite constellation construction, people must find an effective solution to balance the revenue and expenditure of the satellite industry. In today's era, the Internet of Things (IoT) technology [13] has experienced rapid development and popularization with broad market prospects. By 2025, the number of connected IoT terminal equipment is expected to reach 27 billion [14]. As a promising emerging technology, IoT has been widely applied in many scenarios, such as healthcare, transportation, smart cities, smart homes, etc., and it has achieved excellent application performance [15; 16; 17; 18]. While people enjoy the convenient services of IoT, they are also paying for IoT products. IoT offers a wide range of products, covers a wide range of fields, has a large user base, and can provide paid services. Therefore, integrating LEO satellites with IoT services can provide economic support for LEO satellite construction and achieve the economic sustainability of LEO satellite constellations. Not only will the addition of the IoT technology provide economic support for LEO satellite construction, but the global coverage of LEO satellite constellations also contributes to the popularization of IoT technology and products. LEO satellite networks can cover areas with difficult conditions, such as deserts, oceans, etc., which traditional terrestrial networks cannot achieve [19; 20]. IoT terminals in many industries such as transportation (maritime, highway, railway, aviation), maritime monitoring, and farming are located in remote areas without cellular connections [21]; the assistance of LEO satellites can help them solve communication problems. In addition, the infrastructure of terrestrial networks is susceptible to natural disasters such as earthquakes and hurricanes, which can cause communication interruptions in severe cases [11]. Therefore, LEO satellite networks help to eliminate regional restrictions on the use of IoT technology and mitigate the impact of natural disasters on communication. IoT products can provide economic support for LEO satellite construction, and LEO satellite networks can expand the coverage of IoT products. In addition to the complementary relationship between the IoT and LEO satellite constructions mentioned above, the integration of IoT and LEO satellite constellations is also a trend. In traditional ways, due to the powerful computing and storage capabilities, cloud servers are people's preferred choice for providing IoT services. To complete IoT services, cloud servers must receive raw data from terminal devices and then return services.