Real Time Updates medium
Why do developers often use libraries like Socket.IO instead of native `WebSocket` APIs?
- A Native WebSockets are slower.
- B They provide automatic fallbacks (to Long Polling) if WebSockets are blocked, and handle reconnection logic automatically.
- C Socket.IO uses UDP.
- D Native WebSockets cannot send JSON.
Answer: B. They provide automatic fallbacks (to Long Polling) if WebSockets are blocked, and handle reconnection logic automatically.
Reliability. Corporate firewalls sometimes block WS traffic. Socket.IO starts with Long Polling (HTTP) and upgrades to WS if possible. It also handles the complex logic of 'Try to reconnect with exponential backoff' when internet is spotty.
One system design question a day, with spaced repetition so the ones you miss come back.
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