Hard Design: Chat System (WhatsApp/Slack)

What is the 'session affinity' or 'sticky session' problem with WebSocket servers?

— Tests your understanding of this concept.

Answer Options

A Users can only connect to one server forever

B Standard load balancers route WebSocket upgrades incorrectly

C WebSocket connections are stateful — user must stay connected to same server

D WebSocket requires more CPU than HTTP

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