Indonesia Forest Fire Causes Anomalies in Submarine Cable Operations, GeoCables Confirms
Fires in Indonesia
At 10:57 local time on September 4, 2026, a notification was received about a forest fire in Indonesia. The flames have engulfed extensive areas in green zones, posing a threat to local infrastructure and ecosystems. The fire continues, and its consequences may affect both terrestrial and underwater communications in the region.
Cables in the Fire Zone
Within a 500 km radius of the fire zone, several key submarine cables are located. Among them:
- Batam Dumai Melaka (BDM) (353 km from the epicenter, commissioned in 2009, owners - Moratelindo, Telekom Malaysia).
- MIST (8100 km, commissioned in 2024, owner - Orient Link, nearest point - Tuas, Singapore, 427.7 km from the fire).
- India Asia Xpress (IAX) (5791 km, commissioned in 2024, owners - China Mobile, Reliance Jio Infocomm, nearest point - Tuas, Singapore, 427.7 km from the fire).
- I-2SEA (length unknown, nearest point - Tuas, Singapore, 427.7 km from the fire).
- PASULI (40 km, commissioned in 2019, owners - FiberStar, XLSmart, nearest point - Muntok, Indonesia, 102 km from the fire).
- Sumatera Bangka Cable System (SBCS) (57 km, commissioned in 2014, owner - Telkom Indonesia, nearest point - Muntok, Indonesia, 102 km from the fire).
- Jambi-Batam Cable System (JIBA) (267 km, commissioned in 2014, owners - Indosat Ooredoo, Moratelindo, nearest point - Kuala Tungkal, Indonesia, 205.1 km from the fire).
- Link 5 Phase-2 (365 km, commissioned in 2005, owner - XLSmart, nearest point - Kuala Tungkal, Indonesia, 205.1 km from the fire).
What Our Measurements Show
Our monitoring systems have detected significant anomalies on several submarine cables near the fire zone. For Batam Dumai Melaka (BDM), the round-trip time (RTT) increased from 57.2 ms to 195.0 ms, a rise of 137.8 ms (2.6σ relative to baseline). On MIST, RTT rose from 102.5 ms to 192.2 ms (+89.7 ms, 5.3σ), and on India Asia Xpress (IAX) - from 81.5 ms to 202.1 ms (+120.6 ms, 5.1σ). The cable I-2SEA showed the most significant deviation: RTT increased from 110.2 ms to 214.0 ms, a rise of 103.9 ms (14.8σ).
The other cables, such as PASULI, SBCS, JIBA and Link 5 Phase-2, continue to show stable performance, which may be due to their shorter length and distance from the fire zone.
Context and Risks
Anomalies in the operation of submarine cables may be caused by the impact of a fire on terrestrial communication nodes, power supply, or other infrastructure elements related to the cables. Such failures can affect internet traffic routing, especially in Southeast Asia, where these cables play an important role in connecting countries in the region with the global network.
An increase in RTT may lead to delays in data transmission, which significantly affects services dependent on low latency, such as video conferences, online games, and financial transactions. If the fire situation worsens, there may be further degradation of communication parameters.
Further Monitoring
We will continue to monitor the condition of the cables in the fire zone, paying special attention to BDM, MIST, IAX, and I-2SEA, where significant deviations have already been recorded. We will also monitor nearby terrestrial stations and communication nodes to promptly identify new issues.
In case of a fire intensification, additional measures for redirecting traffic to alternative routes may be taken. We will regularly update the data and provide information on any changes in the operation of submarine infrastructure.
