Technical Article

What is a Load Balancer? The load balancer mainly distributes all user requests to the corresponding servers based on the current server load. The advantage of this is to avoid server overload or crash. However, you can also think about it here. If the traffic of the current system is not high, about only a few thousand requests per second, then a load balancer may not be needed. After all, the more complex a system is, the more things need to be considered.

What is DNS? The Domain Name System (DNS) maps human-readable domain names to machine-readable IP addresses. For example, the corresponding IP for google.com is 142.250.191.78. When a user enters a domain name into the browser, the browser must convert the domain name into an IP address through DNS. Once the required IP address is obtained, the user's request is forwarded to the target server.

System components are the basic building blocks of system design. They can be combined to construct complex software systems. Here we will also review the basic concepts of system design. System design is an important link in software engineering, which involves the overall architecture and design of the software system. A good system design can make software systems more reliable, scalable and easy to maintain.

Of course, if you want to use these components to design a system, you must first understand what design components there are? What does each design element represent? This article will introduce each system component, and the following chapters will explain the details and applications of each component in detail.

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.