Hard Design: Chat System (WhatsApp/Slack)

What is the purpose of a Hybrid Logical Clock (HLC) in a distributed chat system?

— Tests your understanding of this concept.

Answer Options

A To synchronize server clocks

B To assign causally consistent timestamps that capture message ordering across nodes

C To measure network latency

D To schedule message delivery

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This question is from the Design: Chat System (WhatsApp/Slack) topic (System Design Cases).

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