State of the Submarine Cables - September 2026
What our distributed measurement network saw in September 2026: every number below comes from our own probes and detectors, and every incident links to its measured timeline.
The month in numbers
- 1 136 208 latency measurements
- 22 940 routes observed
- 35 anomalies detected (9 critical, all investigated and closed)
- 27 cable systems involved
- 45.9 average hours to resolution
Notable incidents
A detected anomaly is not automatically a cable fault: some turn out to be inland routing changes or planned reroutes, and the incident pages say so explicitly.
| Cable | Detected | RTT vs baseline | Outcome |
|---|---|---|---|
| Ulleung-Mainland 2 | 2026-09-26 | - | resolved - measured timeline |
| Jakarta-Bangka-Bintan-Batam-Singapore (B3JS) | 2026-09-17 | 42 -> 92 ms | resolved - measured timeline |
| Ulleung-Mainland 2 | 2026-09-27 | - | resolved - measured timeline |
| Ulleung-Mainland 2 | 2026-09-26 | - | resolved - measured timeline |
| Ultramar GE | 2026-09-18 | 63 -> 334 ms | resolved - measured timeline |
Latency observatory
Slowest and fastest paths among routes with at least 200 measurements this month (average round-trip time).
Slowest observed paths
| Route | avg RTT, ms |
|---|---|
| Ekaterinburg RU - Moscow RU | 3081 |
| Almaty - Tonga Comm Corp | 524 |
| Sevastopol - Tonga Comm Corp | 517 |
| Almaty - Telecom Cook Islands | 481 |
| Almaty - Samoa DataCom | 476 |
Fastest observed paths
| Route | avg RTT, ms |
|---|---|
| Almaty - ns1.nic.kz | 6 |
| Minsk BY - Объект: | 6 |
| Almaty - network probe KG | 7 |
| Minsk BY - Объект: Amsterdam, North Holland | 7 |
| Odessa UA - Зона: Kyiv, Kyiv City AS13335 | 8 |
Month-over-month shifts
Routes whose weighted median moved 15%+ against the previous month (at least 100 samples in both).
| Route | avg RTT, ms |
|---|---|
| Minsk - ns1.md | 121 -> 71 (-41%, faster) |
| Minsk - network anchor#6392 | 227 -> 138 (-39%, faster) |
| Moscow - network probe KG | 68 -> 92 (+35%, slower) |
| Minsk - network anchor#6402 | 165 -> 108 (-35%, faster) |
| Tbilisi - network anchor#6392 | 238 -> 159 (-33%, faster) |
| Sevastopol - network anchor#6431 | 141 -> 187 (+33%, slower) |
Method and reuse
Measurements come from GeoCables own distributed probe network; anomaly detection compares live paths against per-route rolling baselines. Reuse freely under CC BY 4.0 with attribution: raw data in the open dataset, programmatic access via the API, push updates via RSS. Live view: the map.
