The Complete Guide to System Design | Amit Kumar

The Complete Guide to System Design

Why should I learn system design?

Over the last two decades, there have been a lot of advancements in large-scale web applications. These advancements have redefined the way we think about software development. All of the apps and services that we use daily, like Facebook, Instagram, and Twitter, are scalable systems.

Billions of people worldwide access these systems concurrently, so they need to be designed to handle large amounts of traffic and data. This is where system design comes in.

As a software developer, you’ll be increasingly expected to understand system design concepts and how to apply them. In the early stages of your career, learning system design will allow you to tackle software design problems with more confidence and apply design principles to your everyday work.

As you progress through your career and begin interviewing for higher-level positions, system design will become a larger part of your interview process. So, no matter what your level is, system design matters to you.

Because of its increasing importance, we wanted to create a resource to help you navigate the world of system design. This guide details the fundamental concepts of system design and also links you to relevant resources to help you gain a deeper understanding and acquire real-world, hands-on experience.

What is System Design?

System design is the process of defining the architecture, interfaces, and data for a system that satisfies specific requirements. System design meets the needs of your business or organization through coherent and efficient systems.

Once your business or organization determines its requirements, you can begin to build them into a physical system design that addresses the needs of your customers.The way you design your system will depend on whether you want to go for custom development, commercial solutions, or a combination of the two.

System design requires a systematic approach to building and engineering systems. A good system design requires you to think about everything in an infrastructure, from the hardware and software, all the way down to the data and how it’s stored.

System Design fundamentals

Horizontal and vertical scaling

Scalability refers to an application’s ability to handle and withstand an increased workload without sacrificing latency. An application needs solid computing power to scale well. The servers should be powerful enough to handle increased traffic loads There are two main ways to scale an application: horizontally and vertically

Horizontal scaling, or scaling out, means adding more hardware to the existing hardware resource pool. It increases the computational power of the system as a whole. Vertical scaling, or scaling up, means adding more power to your server. It increases the power of the hardware running the application.

There are pros and cons to both types of scaling. You’ll come across scenarios where you need to consider the tradeoffs and decide which type of scaling is best for your use case.

You’ll learn about the benefits and risks of scaling, primary bottlenecks that hurt application scalability, and more.

Microservices

Microservices, or microservice architecture, is an architectural style that structures an application using loosely coupled services. It divides a large application into a collection of separate, modular services. These modules can be independently developed, deployed, and maintained.

Microservices operate at a much faster and more reliable speed than traditional monolithic applications. Since the application is broken down into independent services, every service has its own logic and codebase. These services can communicate with one another through Application Programming Interfaces (APIs).

Microservices are ideal if you want to develop a more scalable application. With microservices, it’s much easier to scale your applications because of their modern capabilities and modules. If you work with a large or growing organization, microservices are great for your team because they’re easier to scale and customize over time.

Proxy servers

A proxy server, or forward proxy, acts as a channel between a user and the internet. It separates the end-user from the website they’re browsing. Proxy servers not only forward user requests but also provide many benefits, such as:

Improved security

Improved privacy

Access to blocked resources

Control of the internet usage of employees and children

Cache data to speed up requests

Whenever a user sends a request for an address from the end server, the traffic flows through a proxy server on its way to the address. When the request comes back to the user, it flows back through the same proxy server which then forwards it to the user

CAP theorem

The CAP theorem is a fundamental theorem within the field of system design. It states that a distributed system can only provide two of three properties simultaneously: consistency, availability, and partition tolerance. The theorem formalizes the tradeoff between consistency and availability when there’s a partition.

Redundancy and replication

Redundancy is the process of duplicating critical components of a system with the intention of increasing a system’s reliability or overall performance. It usually comes in the form of a backup or fail-safe. Redundancy plays a critical role in removing single points of failure in a system and providing backups when needed.

For example, if we have two instances of a service running in production and one of those instances fails, the system can failover to another one.

Replication is the process of sharing information to ensure consistency between redundant resources. You can replicate software or hardware components to improve reliability, fault-tolerance, or accessibility. Replication is used in many database management systems (DBMS), typically with a primary-replica relationship between the original and its copies.

The primary server receives all of the updates, and those updates pass through the replica servers. Each replica server outputs a message when it successfully receives the update.

To be Continued......