Fundamentals of Microservice Architecture: Service Splitting, Registration, Load Balancing, Rate Limiting, and Circuit Breaking

This article, originally written for Shanghai Operations Department in 2019, introduces the basic principles of microservice architecture for beginners.

It explains service splitting principles, using an example of a blog crawler system divided into APIServer, Scheduler, and Crawler services, and discusses horizontal scalability considerations for each component.

The document then covers service registration and discovery, comparing configuration‑file, database, and dedicated registry approaches, and describes how a registry centralizes instance management and health checking.

Load balancing concepts are examined, highlighting that the client decides the distribution strategy, with examples such as Nginx, DNS, and Eureka client.

Subsequently, rate limiting and circuit breaking are introduced using token‑bucket and leaky‑bucket analogies, explaining how gateways enforce these mechanisms to protect backend services.

Finally, the article outlines a self‑built microservice application delivery platform, emphasizing code‑as‑a‑service, automated CI/CD pipelines, and the benefits of a unified deployment solution for large‑scale cloud‑native environments.