The research on resource scheduling technology over Satellite Internet is consistent with the major needs of strategic development in China. In 2020, China officially clarified the scope of “ New Infrastructure” concept,where the “Information Infrastructure” mainly includes “communication network infrastructure represented by 5G, Internet of Things, Industrial Internet, and Satellite Internet”. Particularly, Satellite Internet was included in the category of “New Infrastructure” for the first time. Compared with traditional terrestrial communication networks, Satellite Internet is characterized by global coverage, robust links, and short end-to-end propagation delay. It can be widely applied to scenarios such as data transmission, earth observation, and mobile edge computing. It has great significance
in strategic development. However, Satellite Internet encounters the challenges that representing and scheduling the multi-dimensional resources are difficult. On the one hand, the topology of Satellite
Internet changes with time and the resources are multi-dimensional, heterogeneous and coupling with each other, causing the resources state difficult to represent. Meanwhile, the resource scheduling technology of terrestrial static networks does not apply to Satellite Internet. On the other hand, data transfer only requires link resources in traditional Internet,
while applications have integrated requirements for multi-dimensional resources in Satellite Internet. For instance, earth observation application has the coupled requirements for observation, transmission and storage resources, while the computing applications requires the simultaneous involvement of storage, transmission and computing resources. Existing resource scheduling methods often ignore the complex resource requirements of applications, and split the applications into stages which are scheduled independently. For instance, the earth observation scheduling is always separated into independent earth observation satellites scheduling and data transmission scheduling, causing low utilization of network resources. In addition, existing resource scheduling problems are modeled and solved via mathematical programming methods. This type of methods fall into the algebraic domain, which have disadvantages of long running time and high memory requirements when the network scale is large, unable to schedule resources in real time. Therefore, it is urgent to design an application-driven fast scheduling method for multi-dimensional resources for improving network resources utilization. To satisfy the requirements of real-time multi-dimensional resources scheduling from applications and enhance the network resource utilization in Satellite Internet, we need to study the methods for joint representation of multi-dimensional resource requirements from applications and multi-dimensional resources, and using these methods to design applicationdriven efficient scheduling methods. Towards this, based on time-varying graph theory, this thesis studies the multi-dimensional resources scheduling methods driven by three typical
satellite network applications, to reduce the application completion delay and improve the resource utilization. The main research contents and results of this thesis are as follows: 1. In regards to poor scalability of algorithms for solving data transmission problems over Satellite Internet, this thesis proposed a minimum delay data transfer algorithm in an incremental manner based on time-varying graph theory. The proposed method incrementally solves the problem of joint scheduling of communication and storage resources, via dynamically configuring storage resources. Specifically, this work proposes an incremental minimum delay data transfer algorithm based on the maximum flow algorithm. This method
progressively expands the network scale, taken as input of the problem, during the calculation process, and keeps identifying the network capacity under different network scale until the identified network capacity is no less than the data amount of the task. During the process, the method incrementally solves the problem based on the historical calculation results,
avoiding calculating the network capacity from scratch when network scale increases. The incremental nature of maximum flow algorithms ensures the correctness of proposed method. The time complexity of proposed algorithm is ( · g), reducing (log()) as compared to ( · log() · g) of a classical method. Based on the proposed method, this work further proposed an incremental maximum flow algorithm based on time-expanded
graph, whose time complexity is lower than that of the traditional maximum flow algorithm. Finally, in order to verify the performance of the proposed method, we proposed two variants of the classic minimum delay of data transfer algorithm to compare. Simulation experiments show that the proposed method is highly scalable as the network scale increases or task data amount increases, demonstrating that the joint scheduling of storage and communication resources can effectively improve the algorithm running speed. 2. The earth observation applications in Satellite Internet independently schedule observation, communication and storage resources, causing low resource utilization and long data transfer delay. Regarding this, this thesis proposes an on-demand method for joint
scheduling of transmission and observation resources with high resource utilization. First, this thesis models a generic problem of jointly scheduling observation, transmission and storage resources as a linear programming, which supports on-demand network topology configuration to maximize the amount of successfully transmitted observed data. However, solving this linear programming problem requires a lot of memory and long running
time when network scale becomes large. To tackle this issue, this thesis further used timeexpanded graph to represent the nodes and communication links of the Satellite Internet, and introduced auxiliary vertices and edges to represent the special constraints in the linear
programming problem. Based on this proposed graph, the problem of jointly scheduling observation, transmission and storage resources can be transformed into a maximum flow problem, which can be solved using the proposed incremental maximum flow algorithm. Simulation experiment uses the real trace of the trajectory of Starlink and Gaofen satellites
to construct the network topology, which is the input of the studied problem. The experimental results show that when the traffic load in the network is heavy, configuring the network topology on demand can increase the network throughput by 180%, as compared to predetermined network topology configuration. In addition, when the load in the network is light, the joint scheduling of observation tasks and transmission tasks can increase the network throughput by 100%, as compared with the independent scheduling of observation and transmission tasks. This work proves the necessity of joint scheduling of observation resources and communication resources for earth observation applications. 3. In regards to the difficulty in representing the computing requirements of computing applications in Satellite Internet and the difficulty in scheduling multi-dimensional resources when storage resources are insufficient, computing application completion delay will be long. Thus, this thesis proposes an algorithm to jointly schedule the transmission, computing and storage resources based on a time-varying graph. First, using packets to create decision variables, this thesis models the problem of jointly scheduling transmission tasks and computing tasks under storage constraints as an integer programming problem. This problem first formally gives the mathematical expression of computing applications requirements. To reduce the number of constraints and variables, this thesis integrates multiple packet-oriented variables into a single flow-oriented variable and further proposes a mixed integer linear programming problem based on the constraint transformation method.
However, when the network scale is large, the running time of standard solver is too long to solve the problem. Therefore, an enhanced storage-time aggregation graph model is proposed to jointly represent storage, computing, and transmission resources. Based on this graph model, an application-oriented single-path shortest-delay routing method under storage constraints is proposed. Compared with the traditional routing strategy, this method allows the joint use of storage resources of multiple nodes, thereby reducing the end-to-end transmission delay of applications. The simulation results show that the proposed method can run thousands of times faster as compared to the standard mixed integer linear programming solver, while application delay is less than 10% higher than the theoretical shortest delay. In addition, compared with the classic routing method, the proposed method can reduce the application delay by 20% and increase the network throughput by 40%. It proves the necessity of jointly scheduling storage resources, transmission resources and computing resources for computing applications.