Executive Summary

The SubConnex SCNX3 submarine cable project, designed to enhance connectivity between India and Southeast Asia, is currently in the pre-construction phase, with feasibility studies and environmental assessments underway. Funded by a $3.2 million grant from the United States Trade and Development Agency (USTDA), the environmental impact assessment for the Indian segment began on April 16, 2026, led by WFN Strategies in collaboration with APTelecom and SubConnex. The assessment covers seven sites across India, Thailand, Malaysia, Indonesia, and Singapore, although no official completion date has been announced. The total system cost is estimated at $1 billion, with an initial phase valued at $350 million. The cable is expected to extend approximately 22,000 km, serving around 1.85 billion people. Despite technical and financial planning, no formal government permits have been issued for landing stations in India, and no lease agreements with Indian telecommunications operators such as Bharti Airtel, Tata Communications, or Reliance Jio have been disclosed. The technical capacity of the cable in terabits per second and the portion allocated to India remain unspecified. The announced completion window for the system is 2028-2029.

In parallel, the SEA-ME-WE-5 (SMW-5) submarine cable experienced an 80-hour service interruption at Kuakata, Bangladesh, from 10:00 PM on April 9 to 6:00 AM on April 13, 2026, as confirmed by multiple sources, including Bangladesh Submarine Cables PLC (BSCPLC). The interruption was attributed to an S1.5.1 shunt fault caused by water ingress into the cable’s polyethylene insulation sheath. The repair was carried out during a scheduled maintenance window by the SMW-5 consortium, although no vessels or contractors were disclosed. During the outage, all international traffic was rerouted through the SEA-ME-WE-4 (SMW-4) cable at Cox’s Bazar, which served as the sole alternative route. BSCPLC reported a capacity of 1.7 Tbps for SMW-5 during maintenance, while a capacity of 800 Gbps was indicated for SMW-4; however, conflicting data from previous years suggest a broader range of 3.00 Tbps for SMW-5 and 7.5 Gbps for SMW-4, indicating possible configuration changes. No post-repair technical report was published by either BSCPLC or the consortium. The volume of rerouted traffic and the extent of performance degradation were not quantified in public statements, although users experienced slowdowns, latency, and partial outages. The reliance on a single alternative route underscores the structural limits of Bangladesh’s international connectivity resilience.

Part I examines the ongoing environmental and feasibility planning for the SCNX3 project in India, highlighting the absence of regulatory approvals and commercial commitments despite significant funding and technical development. Part II details the operational impact of the SMW-5 cable maintenance in Bangladesh, emphasizing the vulnerability of regional digital infrastructure to point-source disruptions. Both cases illustrate the interplay between infrastructure planning, technical execution, and systemic resilience in submarine cable networks. The absence of performance metrics, repair documentation, and publicly disclosed commercial agreements in both projects reflects a broader pattern of limited transparency in the deployment and maintenance of critical digital infrastructure.

PART I.

The SubConnex SCNX3 submarine cable project, designed to connect India and Southeast Asia, is proceeding through a series of feasibility and environmental studies funded by the United States Trade and Development Agency (USTDA). The primary landing site in India is Chennai, with additional potential landing points in Malaysia, Thailand, and Indonesia, although specific Indian cities beyond Chennai have not yet been publicly identified. The environmental impact assessment (PESIA) for the Indian segment was initiated on April 16, 2026, by WFN Strategies in collaboration with APTelecom and SubConnex, covering seven sites in India, Thailand, Malaysia, Indonesia, and Singapore. The study is still ongoing and no official completion date has been announced, although one source indicates a projected timeline between 2028 and 2029 for the entire system.

The USTDA has allocated a $3.2 million grant to support the feasibility study for SCNX3, which includes route analysis, engineering design, financial modeling, and regulatory framework evaluation. This funding is part of a broader investment strategy, with the initial phase of the project estimated at $350 million and the total system cost projected at $1 billion. The cable is expected to span approximately 22,000 km, serving about 1.85 billion people in India and Southeast Asia. The project emphasizes resilience, transparency, and secure connectivity, particularly for data-intensive applications such as artificial intelligence and cloud services.

Despite progress in environmental and feasibility planning, no formal government permits have been issued for the construction of landing stations in India. The absence of such approvals indicates that the project is still in the pre-construction phase. Furthermore, no lease agreements with Indian telecommunications operators, such as Bharti Airtel, Tata Communications, or Reliance Jio, have been made public, suggesting that commercial commitments are still pending.

None of the available sources specify the technical capacity of the SCNX3 cable in terabits per second (Tbps). Similarly, the share of capacity specifically allocated to India is not quantified. While the project is described as aimed at improving redundancy and reducing latency for Indian data centers through alternative routing, no measurable data regarding latency improvement or network redundancy gains is provided. The focus remains on long-term infrastructure reliability rather than immediate performance metrics.

Table 1 summarizes the current status of activities at the Indian landing site for the SCNX3 project.

The SCNX3 project represents a major infrastructure initiative aimed at diversifying data connectivity routes between India and Southeast Asia. While preparatory environmental and technical phases are underway, the lack of formal permits and lease agreements with key infrastructure indicates that the start of operations remains subject to regulatory and commercial developments.

PART II.

Maintenance on the SEA-ME-WE-5 (SMW-5) submarine cable at Kuakata, Bangladesh, began at 10:00 PM local time on April 9, 2026, and concluded at 6:00 AM local time on April 13, 2026, resulting in a total service interruption of 80 hours. This period was explicitly announced by Bangladesh Submarine Cables PLC (BSCPLC) through various sources, with consistent indications of the same start and end times. The interruption affected internet connectivity, particularly routes to Singapore, and was accompanied by service degradation, including reduced speeds, increased latency, and partial outages.

The technical fault identified during maintenance was officially classified as an S1.5.1 shunt fault repair, the primary cause of which was attributed to water ingress into the cable’s polyethylene insulation sheath. This classification was confirmed by several sources, including the SAMENA Council and Capacity Global, confirming the type of fault and its physical origin. The repair was carried out by the SEA-ME-WE-5 consortium during the scheduled maintenance window, although no specific ship, repair team, or contractor was publicly identified in any of the available reports.

Despite the operational intervention, the SEA-ME-WE-5 consortium did not publish any post-repair technical report, nor was any made available by BSCPLC. The absence of a formal post-intervention assessment limits the ability to verifiably confirm the long-term stability or performance of the repair. The service interruption was not limited to a single point of failure; it involved the complete rerouting of internet traffic through the alternative SEA-ME-WE-4 (SMW-4) cable at Cox’s Bazar, which serves as the primary node for national connectivity.

Capacity data for the affected cables was reported with some variation. According to BSCPLC, the SMW-5 cable had a declared capacity of 1.7 Tbps during the maintenance period, while a capacity of 800 Gbps was reported for the SMW-4 cable. Other sources indicated a wider capacity range for SMW-5, with a figure of 3.00 Tbps reported in April 2025, and SMW-4 capacity of 7.5 Gbps in 2008, although the latter figure is obsolete and likely reflects a previous configuration. BSCPLC also reported a total national bandwidth capacity of 4.00 Tbps as of August 2025, with an increase of 1 Tbps recorded in the three months preceding the maintenance.

While the volume of traffic rerouted from SMW-5 to SMW-4 was repeatedly reported, no quantitative measure of the transferred data load was made public. The impact on network performance was acknowledged through statements from BSCPLC indicating that users could experience slowdowns, packet loss, and partial service interruptions. However, no specific percentage of national internet capacity loss was declared, nor were estimates provided in public announcements.

The maintenance window, duration, and classification of the technical fault are consistently documented across various sources, confirming a high degree of data consistency. The reliance on SMW-4 as a backup path underscores the structural dependence of Bangladesh’s international connectivity on a single alternative route, with no indication of additional redundancy or alternative routes implemented during the outage.

The most established fact is that maintenance on the SMW-5 cable in Kuakata, Bangladesh, caused an 80-hour service interruption from 10:00 PM on April 9 to 6:00 AM on April 13, 2026, with the fault classified as an S1.5.1 shunt due to water ingress, and traffic rerouted to SMW-4 at Cox’s Bazar, highlighting the fragility of national digital infrastructure in the face of maintenance events at a single point.

Photo by Michael Worden on Unsplash