Forest Fire in Indonesia Impacts Submarine Cable Performance Near Key Landing Points

Fires in Indonesia

At 22:07 local time on October 3, 2026, a large forest fire was reported in the Green Forest area of Indonesia. The fire continues to spread, covering significant areas and threatening regional infrastructure. At this moment, the fire zone is near several key landing points for submarine cables, causing concern regarding their operation.

Cables in the Fire Zone

Within a 500 km radius of the fire zone, there are several submarine cables. Among them:

• Echo (17184 km, RFS 2025, Google, Meta) with landing point in Tanjung Pakis, Indonesia, 347.2 km from the fire.
• INDIGO-West (4600 km, RFS 2019, AARNET, Google) through Jakarta, Indonesia, 350.8 km from the fire.
• Jakarta-Bangka-Batam-Singapore (B2JS) (759 km, RFS 2013, Triasmitra) through Batu Prahu, Indonesia, 117.3 km from the fire.
• Jakarta-Bangka-Bintan-Batam-Singapore (B3JS) (1031 km, RFS 2012, Moratelindo) through Batu Prahu, Indonesia, 117.3 km from the fire.
• Sumatera Bangka Cable System (SBCS) (57 km, RFS 2014, Telkom Indonesia) through Muntok, Indonesia, 142.8 km from the fire.
• PASULI (40 km, RFS 2019, FiberStar, XLSmart) through Muntok, Indonesia, 142.8 km from the fire.
• JaSuKa (-1 km, RFS 2006, Telkom Indonesia) through Bandar Lampung, Indonesia, 236.2 km from the fire.
• Link 4 Phase-2 (300 km, RFS 2005, XLSmart) through Mentigi, Indonesia, 242.5 km from the fire.

Anomalies in Cable Operation

Our measurements show a significant increase in round-trip time (RTT) on two cables:

• On Echo, RTT increased from 117.6 ms to 289.7 ms (difference +172.1 ms, which exceeds the baseline by 9.0σ).
• On INDIGO-West, the delay rose from 198.9 ms to 265.3 ms (difference +66.5 ms, which exceeds the baseline by 5.3σ).

The other cables, including B2JS, B3JS, SBCS, PASULI, JaSuKa, and Link 4 Phase-2, demonstrate stable operation despite their proximity to the fire zone.

Impact on Internet Traffic

Anomalies on the cables Echo and INDIGO-West may lead to increased delays in internet traffic between Indonesia, Australia, and North America. These cables are key routes for international communication, and their temporary degradation could affect data transfer speeds for users and companies. The stability of other cables in the fire zone allows us to minimize the overall impact on the network.

Monitoring the Situation

We will continue to monitor the condition of all mentioned cables, paying special attention to Echo and INDIGO-West, where anomalies have already been detected. In case of further deterioration or new information, we will update this information. Additionally, we will analyze possible changes in traffic routing through neighboring cables.