The space-air-ground integrated network is one of the key directions in the research of 6G network architecture, which aims to achieve seamless global coverage, high reliability and low-latency communication services. One of the core advantages of the network is to provide seamless coverage and stable communication connectivity regardless of the user’s location. By integrating a satellite network with a network of high-altitude platforms, the space-air-ground integrated network is able to compensate for the coverage limitations of traditional terrestrial networks and provide users with reliable communication services, especially in remote areas or in the event of natural disasters. Another important advantage is the high reliability of space-air-ground integrated networks. Since it uses multiple communication nodes, i.e., satellites, high-altitude platforms and ground base stations, the network can still maintain stable operation even if one of the nodes fails or suffers interference. This redundancy and robustness enables the space-air-ground integrated network to cope with a variety of emergency situations and ensure the continuity of communication services.