?? Welcome to Day 8 of our Frontend System Design journey! ??

WebSockets, a key technology in modern web development, revolutionized the way real-time communication happens between clients and servers. At its core, WebSockets facilitate a full-duplex, continuous, and bi-directional communication channel over a single long-lived TCP connection. Today, let's unpack some of its key features, use cases, and challenges.

Features:

?? Handshake: The journey begins with a handshake, where the client requests an HTTP upgrade to initiate the WebSocket connection with the server.

?? Single Connection: Once the upgrade is successful, a persistent TCP connection is established, enabling seamless and uninterrupted communication.

?? Full Duplex: Unlike traditional HTTP, WebSockets support simultaneous two-way communication, allowing data to flow freely in both directions.

?? Security: Just like HTTPS, WebSocket Secure (wss) ensures encrypted and secure communication, safeguarding sensitive data.

?? Framing: WebSocket frames ensure efficient data transmission by breaking down large messages into smaller, manageable chunks.

?? Switching Protocols: With a status code of 101, the server acknowledges the successful protocol switch, marking the beginning of WebSocket communication.

Use Cases:

?? Analytics: Real-time tracking and analysis of user interactions, page views, and application metrics.

?? Financial Trading: Instantaneous updates on stock prices, market trends, and trading activities.

?? Online Gaming: Seamless multiplayer gaming experiences with synchronized actions and real-time updates.

?? Collaboration Tools: Shared editing in documents, spreadsheets, and collaborative whiteboards, akin to Google Docs and Google Sheets.

Challenges:

?? Resource Usage: Balancing vertical and horizontal scaling to manage WebSocket connections efficiently.

?? Connection Limits: Handling large volumes of concurrent connections and preventing overload on servers.

?? Sticky Sessions: Configuring load balancers to maintain session affinity for WebSocket connections.

?? Authentication: Implementing secure authentication mechanisms to authorize WebSocket connections.

?? Firewall/Proxy: Ensuring proper configuration to allow WebSocket traffic through firewalls and proxies.

?? Testing/Debugging: Tools and techniques for testing and debugging WebSocket-based applications effectively.

?? Backwards Compatibility: Gracefully handling scenarios where WebSocket is not available by falling back to long polling or short polling techniques.

?? Resource Cleanup: Properly managing and cleaning up resources to avoid memory leaks and optimize performance.