Technical Article

Back-of-the-envelope, also known as back-of-the-envelope calculation, is a method of calculating approximate values of complex problems using simple estimates.

Let’s also review here. A decentralized system consists of computing nodes connected through a network. These nodes can be various types of servers, such as web servers, application servers, and storage servers.

When designing a decentralized system, it is important to understand the number of requests each node can handle. At the same time, we can also determine the required number of nodes and traffic, so we will use Back-of-the-envelope to calculate our rough estimate, and finally design the system we need.

In modern information technology, system availability (Availability), reliability (Reliability), scalability (Scalability), maintainability (Maintainability) and fault tolerance (Fault Tolerance) are very important non-functional characteristics. These characteristics It not only affects the performance and efficiency of the software system, but also directly affects the user experience. This article will also provide an in-depth explanation of the above five characteristics.

What is abstract? Abstract concepts can help us hide some irrelevant details during system design, allowing us to focus on the overall architecture. It is important to break away from details, because abstraction can hide the complexity within the system design, allowing us to focus more on the results of the system design.

System design is the process of defining various system components, APIs, data models, and integrating the system to accomplish a large-scale system with certain functional requirements. Taking a video broadcasting platform like Youtube as an example, we not only need to consider how to efficiently store and transfer large amounts of video data, but also how to support high concurrency user requirements and how to ensure the stability and scalability of the system.