Understanding System Design: The Key Components You Must Know

System design forms the backbone of software architecture, enabling scalable, reliable, and efficient systems.

In this post, we’ll explore the components of system design, categorized into logical entities and tangible entities.

These components act as the foundational building blocks of any system. Let’s dive deeper.

Logical entities represent the conceptual parts of a system that define its structure and operation. Here are the main logical components:

1. Databases

Data is at the heart of any system. Databases allow us to store and retrieve data efficiently. Common operations include reading, writing, fetching, and storing information.

2. Application Layer

This layer consists of services or applications, such as mobile apps, desktop apps, or websites. Applications provide users with access to the system. These services communicate with databases to perform required operations.

3. Communication Protocols

Communication between machines and applications happens through protocols like HTTP and TCP. At the software level, APIs and RPCs facilitate interaction between services.

4. Presentation Layer

Systems with user-facing interfaces include a presentation layer, such as mobile apps, websites, or desktop apps. However, some systems, like log collectors, may not have this layer.

5. Infrastructure

All these components run on infrastructure provided by cloud platforms like AWS, Google Cloud Platform (GCP), or Microsoft Azure. These providers offer hardware instances where system components operate.

Tangible entities are the concrete technologies and tools used to build the system. Let’s explore them:

1. Databases

       Popular database options include:

• • Relational Databases: MySQL, PostgreSQL
  • NoSQL Databases: MongoDB, Cassandra
  • In-Memory Stores: Redis

2. Application Communication

       Communication happens via:

• • APIs: RESTful or GraphQL endpoints
  • RPCs: Remote Procedure Calls

3. Presentation Layer Technologies

       For building user interfaces:

• • Web Applications: React, Angular, or Vue.js
  • Mobile Apps: Native (iOS/Android) or hybrid frameworks like Flutter

4. Security Mechanisms

Protocols and tools ensure secure data transmission and storage, protecting against cyberattacks.

5. Infrastructure Providers

These include cloud computing platforms such as AWS, GCP, and Azure, offering compute power, storage, and networking.

The components of a system interact as follows:

1. The presentation layer (e.g., a mobile app or website) allows users to interact with the system.
   
   
2. This layer communicates with the application layer, which processes data.
   
   
3. Applications interact with databases for storing and retrieving data.
   
   
4. All components operate on infrastructure (hardware instances) and communicate via communication protocols (network).

Just like a building has walls, floors, and electrical systems, a software system is composed of:

• Applications: Representing the functional parts
• Databases: Storing essential information
• Caches: Enhancing performance
• Load Balancers: Distributing workloads
• Client Interfaces: Enabling user interaction
• Network Requests: Facilitating communication
• Security Layers: Protecting against threats
• Infrastructure: The physical or cloud-hosted backbone

In the next article, we’ll delve deeper into client-server architecture, the cornerstone of modern systems. Stay tuned as we unravel the intricacies of system design, one component at a time!

Feel free to share your thoughts or mention any components we missed in the comments below.