How it works?

WebSockets communicates using the TCP layer. The connection is established over HTTP and is basically a handshake mechanism between the client and server. After the handshake, the connection is upgraded to TCP. Let's see how it works through this flow diagram:

How it works?

The following steps will take you through the flow shown in the preceding diagram:

  1. The first step is the HTTP call that is initiated from the client side; the header of the HTTP call looks like this:
    GET /chat HTTP/1.1
Host: server.example.com
Upgrade: websocket
Connection: Upgrade
Sec-WebSocket-Key: x3JJHMbDL1EzLkh9GBhXDw==
Sec-WebSocket-Protocol: chat, superchat
Sec-WebSocket-Version: ...

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