Australia-Singapore Cable (ASC): latency up to 2.3× normal, 4 Sep 2026
What we measured
| Cable | Australia-Singapore Cable (ASC) |
| Segment | Tanah Merah, SG → Perth, AU |
| Detected | 2026-09-04 23:02 UTC |
| Resolved | 2026-09-11 23:02 UTC |
| Duration | 7d 0h |
| Observed latency | 191.5 ms |
| Baseline | 87.4 ms · 2.26× |
| Increase | +126% |
| Severity | warning |
Who is affected
Countries where Australia-Singapore Cable (ASC) comes ashore, how much of their submarine diversity this cable represents, and what our measurements into them show.
| Country | Dependence on this cable | Other submarine cables | What the measurements show |
|---|---|---|---|
| Australia resilience index: 100 · resilient |
1 of 34 cables (3% of submarine diversity) | APX East, Asia Connect Cable-1 (ACC-1), Australia-Japan Cable (AJC) +30 more | median 193 ms today vs 254 ms over 30 days (474 routes) - faster |
| Christmas Island resilience index: 41 · vulnerable |
1 of 4 cables (25% of submarine diversity) | Bosun, Dhivaru, TalayLink | average 262 ms over 30 days |
| Indonesia resilience index: 100 · resilient |
1 of 73 cables (1% of submarine diversity) | Apricot, Asia Connect Cable-1 (ACC-1), Asia United Gateway East (AUG East) +69 more | median 230 ms today vs 203 ms over 30 days (1061 routes) - unchanged |
| Singapore resilience index: 78 · resilient |
1 of 46 cables (2% of submarine diversity) | APCN-2, Apricot, Asia Connect Cable-1 (ACC-1) +42 more | median 155 ms today vs 163 ms over 30 days (509 routes) - unchanged |
Dependence is structural (share of the country's submarine cables), not a traffic share: real traffic distribution across cables is not public.
Path analysis
Traffic kept the same route. Latency rose without a visible path change, which points at congestion or a fault on the existing route rather than a reroute.
Cross-probe verdict. Other measurements did not confirm the event. We treat this as a probable false positive and label it as such.
Timeline
- Alert 2026090404: warning - ratio 2.26x
- Alert #186 improving: 1/3 consecutive OK
- Alert #186 improving: 1/3 consecutive OK
- baseline_shift: Alert #186 Perth closed as BASELINE SHIFT after 7+ days: frozen 87.4ms -> new baseline 194.8ms (current 191.5ms). Route changed, not a cable incident.
Detection method
Latency is sampled continuously from our probe network. An alert opens when round-trip time to a monitored endpoint holds above its rolling baseline, and closes automatically once it returns. Full method is described on the methodology page.