• The affected systems are SJC2, AAE-1, AAG and TGN Intra Asia, disrupting about 30% of Vietnam's international Internet capacity
  • Viettel added 800Gbps through a usable IA path, was adding 300Gbps on APG and shifted some traffic overland through Laos to Singapore

The fact

Light Reading reported on 31 August that faults on four submarine cable systems — SJC2, AAE-1, AAG and TGN Intra Asia (IA) — had disrupted about 30% of Vietnam's international internet capacity. The problems did not all begin at the same time. VnExpress said AAE-1 had been impaired since February, while SJC2 suffered a new fault on 25 August. AAG and IA were also affected. Repairs to IA were expected to begin in early September, but no repair timetable had been announced for the other three systems.

Viettel said its connections on IA and AAE-1 had been affected. The operator added 800Gbps of capacity on another available IA route and was adding 300Gbps through the Asia-Pacific Gateway. It also moved some traffic onto a terrestrial route through Laos to Singapore, where it planned to add another 1.5Tbps of capacity by the end of August.

The assessment

Viettel's response is less about repairing the damaged cables than keeping traffic moving until those repairs are finished. The operator cannot control when each system returns, but it can decide where to send traffic and how much extra capacity to add on routes that remain available.

The outage exposes the difference between having alternative routes and having enough capacity on them when several cables fail at once. Viettel can use both subsea and terrestrial paths, but those routes still need enough room to take the displaced traffic. The reporting does not show whether the additional capacity has fully removed congestion.

For BTW readers, the real test is whether users continue to feel the outage. If peak-hour slowdowns ease while repairs are still under way, Viettel has created enough room on the surviving routes. If they persist, those routes are still carrying more traffic than they can comfortably handle.

What to watch

Watch whether the 300Gbps APG addition and planned 1.5Tbps on the Laos-Singapore route enter service, and whether Viettel activates more ADC capacity. Repair dates for IA, SJC2, AAE-1 and AAG, together with any reported peak-hour slowdowns, will show whether the temporary capacity is enough to carry traffic until the damaged systems return.