System Design Concepts Course and Interview Prep

This video is a comprehensive guide on system design, emphasizing the importance of understanding the high-level architecture of computers before delving into larger distributed systems. It covers the basics of computer storage including bits, bytes, and more complex units like terabytes. It explains the differences between SSD and HDD storage, highlighting the speed advantages of SSDs. The video also discusses RAM, its use for active processes, and the concept of cache alongside CPU operations.

The next section focuses on the architecture of a production-ready application, starting with the CI/CD pipeline for automated code deployment using platforms like Jenkins. It describes how user requests are managed through load balancers and external storage systems, along with communication between multiple servers. Logging and monitoring systems are crucial for detecting system anomalies, and developers are advised to debug issues in non-production environments.

A discussion on system design principles follows, stressing scalability, maintainability, and efficiency. It highlights the importance of planning for system failures and discusses the CAP theorem's trade-offs between consistency, availability, and partition tolerance. The concept of system availability is linked to SLAs and SLOs, illustrating the goal of high uptime for essential services.

Networking basics are covered, starting with IP addresses and the use of IPv4 and IPv6. It explains how data is transmitted over a network using packets, and the roles of TCP and UDP at the transport layer. The importance of DNS for translating domain names into IP addresses is also mentioned, along with the foundational role of application layer protocols in web communication.

The section on application layer protocols delves deeper into HTTP and its status codes, while explaining the functionality of WebSockets for real-time communication. The video details the use of SMTP, IMAP, and POP3 for email, FTP and SSH for file transfers, and WebRTC and MQTT for real-time communication. RPC is also discussed as a method for executing remote procedures, emphasizing its wide application.

Next, the video explores API design best practices, using an e-commerce platform as an example. It discusses implementing CRUD operations, designing endpoints, and choosing between REST, GraphQL, and gRPC paradigms. The importance of maintaining backward compatibility and setting rate limits is stressed to ensure efficient API performance and user satisfaction.

Caching and content delivery networks (CDNs) are introduced as strategies to reduce latency and improve user experience. The video describes browser, server, database, and CDN caching, detailing how each type helps store data temporarily for quicker access. Different strategies, such as push and pull CDN methods, are covered to highlight their benefits.

Proxy servers, both forward and reverse, serve different functions in managing client-server interactions. Forward proxies assist with privacy and content filtering, while reverse proxies handle load balancing, caching, and SSL termination. The advantages of employing proxies in network management are outlined, including improved security and performance.

Load balancing strategies are detailed, explaining algorithms such as round robin, least connections, and IP hashing. The video describes the importance of continuous server health checks to ensure traffic is directed appropriately. Popular load balancer types, from hardware to software solutions, and their role in preventing system overload are examined.