## 2 System Design and Its Components
### System Configuration and Component Deployment  
In this study, we propose a prototype model for a private cloud service, as shown in Figure 2. We directly build and use the cloud environment using OpenStack. We designed the system with scalability in mind by using a micro-service approach to build each function with separate virtual machines. The private cloud service consists of six independent virtual machines that allow users to upload and manage KOMPSAT images and process them simultaneously. Figure 1: Conceptual diagram of a multi-cloud service based on the ODC platform. Figure 2: Microservice design of the multi-cloud environment for the integrated management and utilization of KOMPSAT based on ODC. The Database service manages all data using PostgreSQL [43] and PostGIS [44] as relational database services. On the other hand, the Core & Explorer service stores and manages data in a time series format as an ODC platform service. The Jupyter service, which allows internal users to process and use the data in conjunction with ODC, provides each user with a virtual environment. These virtual machines can be replicated based on the initial build, allowing for rapid deployment to multiple users within the acceptable limits. The Shared Storage service is a file-sharing service provided within the private cloud, and satellite images are stored and shared with internal systems through communication that is disconnected from external systems. The ARD generation process service is a SaaS with modules for uploading and processing data. Data management users upload and manage data through SaaS, and the interface establishes data linkage with the public cloud. Finally, the Synchronous System links data to AWS S3 and requests data registration with ODC provided by the public cloud service. To create a unified system, the database and data must be provided in a shareable format over the internal network. Therefore, an OpenStack Self-Service Network was established to create an internal network that allows all services to communicate with each other. The public cloud service provided by AWS offers various services and comprises four services. The Relational Database Service (RDS) and Core & Explorer services were configured similarly to the private cloud service, as ODC is also used in the public cloud. This study performed indexing data through Core & Explorer for simple web browsing, but the ODC platform supports additional functions. Other ODC services provide further explanation and offer various services that provide web-based time-series visualization and processing for external users. AWS provides a number of services that use the latest technology to store large amounts of data quickly and reliably. Among these services, S3 provides storage for large data such as LANDSAT and Sentinel. The ODC is designed for cloud-based services, enabling data management through object storage access. Therefore, this study utilized the storage and sharing method to store and share satellite images connected to the private cloud through S3. Only administrators who synchronize data through the AWS Identity and Access Management (IAM) service can access S3. As KOMPSAT data is not free like LANDSAT data, the service is limited to external users who download the data directly. ODC Core is an open-source data cube framework for storing, managing, and analyzing large-scale geospatial data. It stores geospatial data in a multidimensional array format, allowing for fast retrieval and analysis. These multidimensional arrays are designed to match the characteristics of geospatial data with arbitrary dimensions such as x, y, time, and others. ODC Core supports various geospatial data formats, enabling efficient data management from different sources. It also supports a distributed computing architecture for processing large amounts of data. ODC Core is written in Python and uses various open-source libraries and frameworks such as NumPy, PostgreSQL, and Apache Spark. It is distributed under the Apache 2.0 license, allowing free use.