WebSockets: Advantages and Disadvantages Explained

This article explores the pros and cons of using WebSockets compared to HTTP, especially in the context of IoT (Internet of Things).

What are WebSockets?

WebSockets are a technology enabling bidirectional communication over a single TCP socket, functioning as a type of PUSH technology. It’s a protocol that establishes full-duplex communication channels over a single TCP socket. While designed for web browsers and servers, it can be used by any client or server application.

The image above illustrates the message exchange between a client and a server using WebSockets. As shown, WebSockets employ handshake messages to establish a connection, unlike HTTP’s request-response messaging mechanism. HTTP is half-duplex, while WebSockets are full-duplex. This allows developers to open a persistent connection and transmit data in real-time between a client and a server. Messages can be sent simultaneously or back and forth across this single TCP socket connection.

Benefits of WebSockets over HTTP

Here are the key advantages of using WebSockets instead of HTTP:

• Duplex Communication: Supports two-way communication, allowing both the client and server to send data simultaneously.
• Faster Data Transfer: WebSockets enable faster and more immediate data sending and receiving compared to HTTP. They are also faster than AJAX.
• Cross-Origin Communication: While potentially posing security risks, WebSockets allow communication between different domains.
• Cross-Platform Compatibility: Works across various platforms like web, desktop, and mobile.
• Reduced Overhead: HTTP can have up to 2000 bytes of overhead, whereas WebSockets only require about 2 bytes.
• Replaces Long Polling: Eliminates the need for long polling techniques.
• Data Typing: WebSockets are data-typed, whereas AJAX calls can only send string data types.

Drawbacks of WebSockets

Here are the limitations and disadvantages of using WebSockets:

• HTML5 Compliance: Requires the web browser to be fully HTML5 compliant.
• No Success Functions: Unlike AJAX, WebSockets lack built-in success functions.
• No Intermediary Caching: Caching at intermediary points or the edge is not possible with WebSockets, unlike HTTP.
• Limited HTTP Features: Building a custom protocol with WebSockets doesn’t allow leveraging friendly HTTP statuses, body, etc.
• Simpler Alternatives: If the application doesn’t require substantial dynamic interaction, HTTP may be simpler to implement.