round-trip propagation floor added by 1,000 km of fiber, before any switching or queuing
~10 msobserved
| Value kind | observed — Reported measurements, counts, and specifications keep the precision and scope stated by their source; an exact specification is not treated as a range. |
|---|---|
| As of | 2025 |
| Source | M2 Optics; fiber-latency physics · Rule of thumb: 4.9 microseconds per kilometer one-way, or about 9.8 milliseconds round-trip over 1,000 km, before equipment delays. |
| Review | checking…review by 2026-10-23 · standard cadence |
| Recorded changes | last 2026-06-29 |
| Claim id | round-trip-propagation-floor-added-by-1-000-km |
Where the guide uses it
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