But for real-time communication, we cannot afford any delay. HTTP is a stateless protocol that means every time we make a request, a three-way handshake is performed, which increases the delay in response. There is one-way communication between the client and server because HTTP is a unidirectional protocol. After the data transfer is complete, the connection is closed. The HTTP protocol is an application protocol that uses the TCP protocol, which requires a three-way handshake to connect the client and the server successfully. We know that we use an HTTP request to transfer any message/data from our client to a server. But did you ever thought about how these realtime-applications built? It’s because of Socket.IO Let's start with server code and let's install all the necesarry libraries.We all are familiar with real-time messaging applications and use them quite often. Socket.IO is quite popular and it is used by Microsoft Office, Yammer, Trello.Īltough this tutorial is provided in series, this specific tutorial is standalone so no previous code needs to be included. This means that whenever an event occurs, the server can push messages to clients so the client gets notified immediately and vice versa. Sockets are an easier and faster solution which most real-time systems are designed on which provides bi-directional communication channel between a client and a server. It involves polling the server for changes and by design it is very slow and requires more resources. Writting a real-time application without WebSockets, using HTTP requests, has been traditionally very hard. applications like Google docs which allows multiple people to update the same document simultaneously.instant messaging system - Chat apps like WhatsApp, Facebook Messenger etc,.

Some examples of real-time applications are: Socket.IO is built on top of WebSockets API and Node.js.Ī real-time application (RTA) is an application that functions within a period that the user senses as immediate. Socket.IO enables real-time event-based communication in both directions (client and server side).

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