A protocol providing a persistent, full-duplex communication channel between client and server over a single TCP connection.
In modern web and mobile applications, WebSockets enable real-time features (like chat, live notifications, and collaborative editing) without repeatedly polling the server. They reduce latency and bandwidth overhead by eliminating the need for HTTP request/response cycles after the connection is established.
Use WebSockets when you need low-latency, bidirectional communication for real-time updates between clients and servers.
You need to know
Handshake Upgrade - Starts as an HTTP request that “upgrades” the connection to WebSocket, negotiating a persistent TCP link.
Full-Duplex Messaging - Once upgraded, both client and server can send text or binary messages independently at any time.
Connection Lifecycle - You must handle connection open, message receipt, errors, and clean closure to avoid resource leaks.
Popular technologies
Socket.IO - JavaScript library that abstracts WebSockets and fallbacks, offering features like automatic reconnection and rooms.
uWebSockets - High-performance C++ WebSocket server library optimized for low latency and high concurrency.
AWS API Gateway WebSockets - Managed service for deploying scalable WebSocket APIs with built-in routing and authorization.
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