System Design Interview – Chat Service (Facebook Messenger / Whatsapp)

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January 26, 2023

Distributed Systems  System Design Interview 

High-Level Overview

The chat service system is a platform that allows users to communicate with each other in real time. It can be used for both one-on-one conversations and group conversations. The system consists of a client-side application (e.g. Facebook Messenger or Whatsapp) and a server-side application.

Client-Side Application

The client-side application is responsible for providing the user interface and handling user interactions. It is responsible for displaying messages, allowing users to send messages, and managing the conversation state.

Server-Side Application

The server-side application is responsible for managing user accounts, storing messages, and routing messages between users. It also handles authentication and authorization, as well as provides APIs for third-party applications to integrate with the chat service.

Data Storage

The chat service system stores data in a database. This includes user accounts, messages, and conversation states. The data is stored in a relational database, such as MySQL or PostgreSQL.

Message Routing

The server-side application is responsible for routing messages between users. When a user sends a message, the server-side application will look up the recipient’s account and route the message to them.

Third-Party Integration

The server-side application provides APIs that allow third-party applications to integrate with the chat service. This allows users to send messages from other applications, such as games or productivity tools.

Security

The chat service system implements security measures to protect user data. This includes authentication and authorization, as well as encryption for messages in transit.

*** Created by ChatGPT on Jan 26, 2023.