South Atlantic Cable System (SACS): latency up to 2.2× normal, 20 Jul 2026
What we measured
| Cable | South Atlantic Cable System (SACS) |
| Segment | Fortaleza, BR | Sangano, AO → Sangano, AO | Fortaleza, BR |
| Detected | 2026-07-20 07:31 UTC |
| Resolved | 2026-07-28 00:01 UTC |
| Duration | 7d 16h |
| Observed latency | 124.4 ms |
| Baseline | 64.5 ms · 2.18× |
| Increase | +130% |
| Severity | warning |
Who is affected
Countries where South Atlantic Cable System (SACS) 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 |
|---|---|---|---|
| Angola resilience index: 80 · resilient |
1 of 5 cables (20% of submarine diversity) | 2Africa, SAT-3/WASC, Unitel North Submarine Cable (UNSC) +1 more | no measurement today; median 193 ms over 30 days (3 routes) |
| Brazil resilience index: 100 · resilient |
1 of 26 cables (4% of submarine diversity) | America Movil Submarine Cable System-1 (AMX-1), Brazilian Festoon, BRUSA +22 more | median 144 ms today vs 152 ms over 30 days (378 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. Our own cross-check concluded this was an operator reroute, not a cable fault. We publish it anyway, labelled as such.
Timeline
- Alert 2026072002: warning - ratio 2.18x
- Alert #154 improving: 1/3 consecutive OK
- Alert #154 improving: 2/3 consecutive OK
- Alert #154 resolved: RTT 124.39ms (baseline 64.49ms), 3 consecutive OK
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.