Polling vs Server-Sent Events (SSE) vs WebSockets | System Design with Microsoft SWE скачать в хорошем качестве

Polling vs Server-Sent Events (SSE) vs WebSockets | System Design with Microsoft SWE

Real-time communication is one of the most misunderstood topics in system design. In this video, I will explain Polling, Long Polling, Server-Sent Events (SSE), and WebSockets — not just what they are, but why they exist, how they work internally, when you should use each one in real systems, and engineering tradeoffs. I will go beyond surface-level explanations and focus on mental models, protocol-level behavior, and real-world tradeoffs, using simple diagrams and real-life examples to make everything intuitive. You’ll learn: Why HTTP is not real-time by default How Long Polling actually works under the hood What text/event-stream means and how SSE delivers updates How the WebSocket handshake works (headers, upgrade, frames) The pros and cons of Polling, SSE, and WebSockets Time Stamps: 00:00 – Intro 00:11 - Original Web Model 01:10 – The Problem with Traditional HTTP 02:29 – What Is Polling 05:33 – Pros & Cons of Polling 06:40 – Why Server-Sent Events (SSE) Were Introduced 07:27 – How SSE Works (event-stream explained) 10:25 – Pros & Cons of SSE 12:33 – SSE Response Header 13:28 – What Are WebSockets? 14:51 – WebSocket Handshake (Headers & Upgrade) 18:38 - Pros & Cons of WebSockets 20:14 – Long Polling vs SSE vs WebSockets (Comparison) A clear comparison to help you choose the right approach This video is especially useful if you are: Preparing for System Design interviews A backend or full-stack developer Building or designing real-time applications