🖥️

Client-Server

Traditional Request-Response Model

The most traditional and widely used architecture. It follows a unidirectional flow where the client sends a request and the server responds, with HTTP/HTTPS being the most representative protocol.

Architecture Diagram

🌐
Browser
📱
Mobile App
Request →
← Response
🖥️
Server
API / Web Server
↔
🗄️
Database
Flow Description
  1. Client sends HTTP request to server
  2. Server receives request and executes business logic
  3. Query/store in database as needed
  4. Server returns response to client

How It Works

1

Client sends HTTP request to server (GET, POST, etc.)

2

Server receives and processes the request

3

Server queries database / executes business logic

4

Server returns HTTP response to client

Pros

  • ✓ Simple to implement
  • ✓ Easy to debug
  • ✓ Caching can be utilized
  • ✓ Standardized protocols

Cons

  • ✗ Server can become a bottleneck
  • ✗ Difficult to do real-time updates
  • ✗ Service disruption when server goes down
  • ✗ Client must always initiate the request

Use Cases

Web applications (Browser ↔ Web server) REST API GraphQL API Mobile app backend
🔌 WebSocket →