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Submarine Cable Status
Methodology

How Submarine Cable Status works

Sources first

Every operational claim on Submarine Cable Status links to a source: that a cable is faulty, where the fault is, which vessel is repairing it, when it will be fixed. If we cannot cite it, we do not state it.

Each incident has one of three evidence levels:

  • Confirmed: the cable’s owner, operator or consortium, or another authoritative party, has said there is a fault.
  • Suspected: at least two independent kinds of signal agree (for example a routing change plus a credible report), but nobody authoritative has confirmed it.
  • Observed: network measurements look abnormal. We show these as telemetry and never as a cable fault.

How we rate sources

Sources are rated authoritative, reliable or unverified. Ratings can differ by cable: an operator is authoritative for its own systems but only reliable for someone else’s. Each citation keeps the rating the source had when we linked it.

How incidents are compiled

Editors compile incidents from operator notices, ISP status pages, maritime notices and established trade press, and link every source. Where we enable automated monitoring, software only drafts suggestions. A person checks every draft against the original source before anything is published. Software never publishes on its own.

When a source gives only a distance (for example “about 615 km from the Singapore landing station”), we place an approximate marker along the published route and draw a wide radius around it. The incident page says when a location is derived this way.

Cable data

Cable routes, landing points, owners, lengths and ready-for-service dates come from TeleGeography’s Submarine Cable Map dataset (CC BY-NC-SA 3.0). Routes are drawn by TeleGeography and are approximate. Land, borders and country names come from Natural Earth (public domain).

Network telemetry

We use Cloudflare Radar’s outage annotations and latency data, and measure routes between major cities with RIPE Atlas. We flag an anomaly only when several probes on different networks show a sustained change: at least +15 ms and +20% over the 28-day baseline for 15 minutes or more. Traffic can reroute for many reasons, so an anomaly is never proof of a cable fault.

History and corrections

Incident timelines are append-only. When an ETR changes, the old estimate stays visible. When we get something wrong, we add a correction entry instead of editing the record quietly.

Report an incident or correction

Send us a link to a public source. Reports go into our review queue, and we publish nothing without a source we can verify.

Data and licensing

Cable routes are approximate and must not be used for navigation, marine works or anchoring decisions. Cable data © TeleGeography, licensed CC BY-NC-SA 3.0 (non-commercial, share-alike). Cloudflare Radar data is CC BY-NC 4.0. Our own incident records are CC BY 4.0: reuse them freely, but credit “Submarine Cable Status” with a link. The site’s design, code and branding are not openly licensed (see the terms). Third-party material is quoted briefly and linked, not republished. Operator network maps appear only where the operator has given written permission.