Unlock the full power of real-time web communication by building a standards-compliant WebSocket server from the ground up. This hands-on course offers an immersive deep dive into the WebSocket protocol using Node.js, helping you truly understand what happens behind the scenes during client-server messaging. By the end of the course, you'll be equipped to implement bidirectional data flow in your own apps with precision and confidence.



Recommended experience
What you'll learn
Manually implement the WebSocket handshake protocol, including SHA1 and base64 encoding
Parse and process raw WebSocket data frames using buffers and bitwise operations
Construct and send WebSocket messages from server to client with protocol-compliant headers
Handle connection closure, masking issues, and ping/pong logic as per RFC 6455
Skills you'll gain
Details to know

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May 2025
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There are 6 modules in this course
In this module, we will explore the foundations of WebSocket communication, including how the protocol upgrades from HTTP to enable persistent, two-way connections. We’ll also cover the critical role RFC 6455 plays in ensuring compatibility and protocol integrity. This section sets the groundwork for building an authentic WebSocket server.
What's included
2 videos1 reading
In this module, we will build a functional Node.js HTTP server from the ground up. We'll set up the client-side interface, structure our server-side code using custom modules, and implement error handling with debugging support. These steps prepare us for seamlessly introducing WebSocket capabilities.
What's included
6 videos1 assignment
In this module, we will focus on initiating a WebSocket connection by listening to the HTTP upgrade event. We’ll break down client headers, use Node’s crypto module to generate a valid Sec-WebSocket-Accept key, and validate the handshake process. Testing ensures our server can establish real-time communication with any compliant client.
What's included
9 videos1 assignment
In this module, we will dive deep into the anatomy of WebSocket frames. From extracting and unmasking payloads to parsing frame headers with bitwise operations, we’ll cover how the server receives and processes both small and large messages. Debugging tools will assist in refining the logic for real-time, binary-safe communication.
What's included
34 videos1 assignment
In this module, we will construct and send WebSocket frames from server to client. We’ll handle everything from setting FIN and OPCODE bits to encoding payloads and managing variable-length headers. By the end, our server will be capable of echoing messages and handling client responses with precision.
What's included
11 videos1 assignment
In this module, we will master the process of closing a WebSocket connection. From detecting ping/pong and malformed frames to analyzing closure behavior via the CloseEvent object, we’ll build a fully RFC-compliant server closure workflow. We'll also address edge cases like unmasked data and large payload termination.
What's included
16 videos2 assignments
Instructor

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Frequently asked questions
Yes, you can preview the first video and view the syllabus before you enroll. You must purchase the course to access content not included in the preview.
If you decide to enroll in the course before the session start date, you will have access to all of the lecture videos and readings for the course. You’ll be able to submit assignments once the session starts.
Once you enroll and your session begins, you will have access to all videos and other resources, including reading items and the course discussion forum. You’ll be able to view and submit practice assessments, and complete required graded assignments to earn a grade and a Course Certificate.
More questions
Financial aid available,