WebSockets: Introduction And Usage

Introduction to WebSockets, its usage, and why to use PieSocket's managed WebSocket Server API

WebSocket is a computer communication protocol that operates over HTTP, and it provides a two-way communication channel between a client and a server. It works over the HTTP protocol and is implemented using the “HTTP upgrade header.”

What Is WebSocket?

WebSocket is a real-time version of HTTP. While HTTP needs the client to send a request every time for communication. WebSocket allows the server to send data to the client on a long-lived connection that stays open for a long time.

In short, any URL that starts with “ws://” (non-secure) or “wss://” (secure) points to a WebSocket Server. They usually operate on ports 80 and 433, respectively.

Usage of WebSockets

Imagine a scenario where you want to inform a user on your website or app, for a change on the server or database without reloading the whole page/screen.

You can either use HTTP polling (making REST API calls each x second to fetch status) or WebSockets.

WebSockets are way more efficient than HTTP polling in following ways:

  • Less memory/CPU usage
  • Fewer Internet data usage
  • Faster than polling
  • Easier to implement

Unlike HTTP requests, a WebSocket connection stays open, and the server can send downstream data to the client anytime during the connection lifetime.

You can see WebSockets in use on almost every interactive modern website or app. Few examples are Facebook chat, Location tracking apps, Stock market monitoring websites, etc.

Image: How WebSocket Works

The image above shows how data between two clients is synchronised without a full page reload through the WebSocket server connection.

How to use WebSockets

Two components create a WebSocket system.

  • A WebSocket client
  • A WebSocket server

WebSocket Client

Your browser is the best example of a WebSocket client. All modern browsers support WebSocket API, which is used to connect to a WebSocket server.

Tutorial: How to use WebSocket with Javascript

If you wish to implement WebSocket with a mobile app, WebSocket client libraries are available for AndroidiOS.

You can develop a custom WebSocket client for any platform that supports HTTP/TCP protocol connections.

WebSocket Server

A WebSocket server is a process running on your system that listens to WebSocket connections and handles the communication with clients trying to connect to it.

There are many libraries available that can help you build a WebSocket server. Following is a list of a few:

Google ” WebSocket server,” and you will probably find an existing library to implement a WebSocket server.

While it is easy to create a WebSocket server, it’s hard to maintain one. If you want to save yourself the time to set up and maintain a scalable WebSocket server cluster, you can use PieSocket’s WebSocket Server API.

Best WebSocket Providers

Scaling a WebSocket server is a complex job and it requires all the nodes in the network to communicate between them to properly broadcast the message to all clients connected to all the nodes in a cluster.

A fully-managed service like PieSocket is recommended if you wish to use reliable WebSocket service in production, for following reasons:

  • Cheaper than in-house solutions.
  • On-premise installation.
  • No-log policy gives you complete control over your data.
  • Auto-scalable, tried and tested clusters.
  • Quick to get started with
  • Ready to use APIs and SDKs.

There are other Alternatives to PieSocket, like Pusher and Ably. However, PieSocket costs 50% less than what these services cost for the save set of features.

Here is how to create a realtime chatroom with WebSocket using PieSocket’s WebSocket API in under 5 minutes.

A WebSocket URL from PieSocket looks like this:

You can learn more about all the parameters and supported features on the WebSocket Documentation page.

In the give WebSocket URL above you need to use an API key.

You can use the demo API key provided by PieSocket to test the service even without creating an Account, or get your own API key.

Testing WebSocket Servers

The team at PieSocket has built a very handy tool to test any WebSocket server.

You can use the: Online WebSocket Tester to test secure WebSocket endpoints.

If you wish to test un-secure (ws://) connection, you can use the chrome extension for the same tool.

Using this tool you can send messages to a WebSocket server and view logs of all the incoming messages in the console.

WebSocket VS MQTT

MQTT is a technology which can be used as alternative to WebSocket. MQTT works on the pubsub methodology and is best suited to IoT communications.

Following table describes major differences between the two technologies.

WebSocket MQTT
There is no concept of priorityAbility to set priority
Used mainly for web-applications, even though
it supports mobile and IoT platforms.
Mainly used in client server applications and IoT devices.
Low latencyHigh latency compared to WebSocket.
No concept of topics (Available through PieSocket)Works on the concept of pubsub topics.

If you are trying to decide which one is better, the answer is not a simple yes or no. It depends upon factors like, which platform does your application use, what is the type of users, type of data to be transmitted, under which conditions and so on.

If you are struggling to decide which suits best for your particular use case, talk to PieSocket experts using the chat button given at the bottom right of this page. Someone from our team will help you asses the best option for your application.

WebSocket Authentication

WebSocket does not come with inbuilt authentication and an authentication system needs to be implemented by your developers if you are building an in-house solution, so hackers and attackers do not misuse the server or take it down.

if you are using PieSocket’s managed WebSocket API, authentication is available out of the box. You can add authentication headers and use private channels to make sure the data being transmitted is

  1. Sent by a trusted user.
  2. Received only by a trusted user.

To read more about how to add authentication to your WebSocket Channel, please see our WebSocket Authentication guide.

Hope this article help you in your WebSocket journey, feel free to talk to us with any queries or leave a comment using the comment box below.