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What is WebSocket?

Rizwan Rasheed

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An overview of WebSocket

The WebSocket protocol is a TCP-based network protocol that specifies how data is transferred between networks. Almost all clients utilize this network protocol since it is so dependable and efficient. TCP is a protocol that establishes communication between two endpoints, often known as sockets. Two-way connections, such as WebSocket allows for data to flow in both ways at the same time., causing data to be retrieved more rapidly. WebSocket, in particular, allows a web application to communicate directly with a WebSocket server. To put it another way, you can bring up a web page and have it shown in “real-time.”

How does WebSocket work?

First, consider how websites are accessed without the use of WebSockets. Web pages are often transmitted over the Internet via an HTTP connection. The protocol is used to transfer data so that the website may be shown on your browser. For this to happen, the client makes a request to the server for each action you do. When using HTTP to access a website, the client must first submit a request to the server. The server then responds by sending the requested connection. To put it another way, HTTP operates on a basic request-and-response architecture, which results in a substantial latency.

Things are different with the WebSocket protocol. Websites may now be called up in real-time, utilizing a dynamic call-up method. All the client has to do is establish a connection with the server by transmitting the handshake for the WebSocket protocol. This handshake provides all of the necessary identifying information for data transmission.

The channel remains open after the handshake to allow for near-constant communication. This means that the server can deliver data on its own without requiring the client to request it. So, if the server receives new data, it delivers it to the client without requiring the client to make a special request.

This idea is used in push notifications on websites.

To begin communication, the client submits a request, just as with HTTP. But after that, a TCP connection is maintained. The following is the content of the handshake between the client and the server:

The client sends the request:

GET /chatService HTTP/1.1
Upgrade: websocket
Connection: Upgrade
Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==
Sec-WebSocket-Protocol: soap, wamp
Sec-WebSocket-Version: 13

The server answers:

HTTP/1.1 101 Switching Protocols
Upgrade: WebSocket
Connection: Upgrade
Sec-WebSocket-Accept: s3pPLMBiTxaQ9kYGzzhZRbK+xOo=
Sec-WebSocket-Protocol: wamp

When should you use WebSocket?

When speed is critical, WebSocket comes in. Any application that requires a high-speed, low-latency connection should use WebSocket. Some examples of when WebSocket is used are:

  • live chats on support websites
  • news tickers
  • stock tickers
  • messaging applications
  • real-time games
  • social networking sites to enable live engagement and immediate chat between users

Standard connection requests are no longer sufficient for most businesses nowadays.


WebSocket technology is designed to make the web quicker, safer, and more dynamic. It’s a fast protocol that’s essential for current web apps that demand quicker interactions than the standard HTTP connection can provide. However, HTTP should not be abandoned; despite WebSocket’s existence, HTTP is still a significant internet protocol.


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Rizwan Rasheed
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