NTP vs PTP for Time Sync

NTP (Network Time Protocol) and PTP (Precision Time Protocol) are time synchronization methods; NTP provides millisecond accuracy for general systems, while PTP achieves sub-microsecond precision for specialized, high-performance networks.

When to Use

Use NTP for web servers, databases, and enterprise apps where millisecond accuracy is acceptable. Use PTP for telecom, financial trading, or distributed control systems needing ultra-precise clock sync.

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A SaaS platform syncs its servers with NTP to keep logs consistent, while a stock exchange uses PTP to timestamp trades accurately within microseconds.

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Why Is It Important

Accurate time is essential for event ordering, debugging, and security in distributed systems. Inconsistent clocks can cause data corruption or compliance issues.

Interview Tips

Explain NTP vs. PTP in terms of accuracy vs. complexity. Show you know when to choose one over the other, and use relatable examples (e.g., cloud servers vs. trading systems).

Trade-offs

NTP is simple, scalable, and broadly supported, but less precise. PTP delivers high accuracy, but requires specialized hardware and more complex setup.

Pitfalls

Using PTP without hardware support won’t yield benefits. Over-engineering with PTP when NTP is enough wastes resources; under-engineering with NTP in precision systems risks failure.