DB4 is part of the Luguang IoT framework developed by Beijing Liguang Technology Co., Ltd. It is a Distributed Database Service Platform with high performance, distributed storage and distributed high availability architecture. It uses distributed storage architecture, provides consistent service to multiple endpoints and provides real-time data high availability. It provides a variety of services such as distributed storage, distributed reliability system, distributed cache, distributed messaging and distributed monitoring. It also provides high-performance SQL and NoSQL query functions, supports multi-dimensional data storage and analysis, and ensures data security. It is a comprehensive distributed storage and distributed database service that can meet the needs of various scenarios.