TL;DR WebSocket
A WebSocket is a communication protocol that provides a persistent, full-duplex connection between a client and a server over a single TCP connection. Unlike standard HTTP where the client sends a request and waits for the server to respond before the connection closes, a WebSocket connection stays open and allows both the client and server to send messages to each other at any time without a new request being needed. This makes WebSockets the right choice for any application that requires real time communication, such as live chat, collaborative editing, multiplayer games, live dashboards, and financial data feeds. WebSockets are initiated via an HTTP upgrade request and then operate over their own protocol. CloudSonic supports WebSocket connections out of the box on all application hosting and API hosting plans. The Nginx configuration handles WebSocket proxying correctly by default so no additional setup is needed on your end.
How WebSockets Work
A WebSocket connection begins as a standard HTTP request. The client sends an HTTP request with a special Upgrade header indicating it wants to switch protocols. If the server supports WebSockets it responds with an HTTP 101 Switching Protocols status and the connection is upgraded from HTTP to the WebSocket protocol. From this point the connection remains open and both the client and server can send messages to each other at any time without a new request being required. Messages can be text or binary data and are framed with a small header that indicates the message type and length. Either party can close the connection by sending a close frame. This persistent bidirectional connection is what makes WebSockets suitable for real time applications. A chat application can push new messages to all connected clients the instant they arrive. A live dashboard can push updated metrics every second. A collaborative editor can synchronise changes between users as they type. None of these would be practical with standard HTTP request-response cycles.
Why WebSockets Matter for Your Website
For most traditional websites and blogs, WebSockets are not relevant and standard HTTP request-response cycles are perfectly adequate. WebSockets become essential when your application needs to push data to users in real time without those users having to request it. A live chat widget that shows messages as they are sent, a collaboration tool that synchronises edits between users, a sports score tracker that updates without page refreshes, or a trading dashboard that shows live price movements all require a persistent connection that can deliver data the moment it is available. The alternative to WebSockets for these use cases is polling, where the browser sends a new HTTP request every few seconds asking if anything has changed. Polling is inefficient, slow, and creates unnecessary server load. WebSockets replace polling with a single persistent connection that the server can use to push updates instantly, delivering a genuinely real time experience at a fraction of the server cost.
