Undersea Networks: Submarine cables driving the digital transformation

In a world where information travels faster than people, digital connectivity has become the invisible thread that ties economies, communities and opportunities together. Whether it is remote islands or bustling coastal towns, reliable connectivity is now a lifeline for growth, innovation and everyday life. Submarine cables, stretching over 1.4 million km across oceans, are silently driving this transformation, linking continents, supporting trade, powering emerging technologies, unlocking new avenues for economic expansion and supporting the global energy transition. In India, their deployment has played a significant role in digital transformation, bringing high-speed connectivity to the remotest parts of the country including islands, connecting underserved communities, and helping local economies grow and thrive. As we move closer to becoming a $5 trillion digital economy, these cables serve as an undeniable foundation that not only fuels economic growth, but also enables advanced technologies such as artificial intelligence (AI), internet of things and cloud computing to thrive.

Currently, four interlinked factors are fundamentally reshaping the submarine cable ecosystem, redefining who invests, the associated demand, the evolution of technology and the integration of sustainability as a core consideration.

India is poised to be at the forefront of a new wave of undersea connectivity, with an expected investment of approximately $13 billion in new submarine cable projects to be initiated during 2025-2027. International capacity to and from India is projected to increase to 148 terabits per second. While cloud providers such as Meta, Google, Microsoft and Amazon are taking the lead in many of these route decisions, new cables are being designed for higher capacity, lower latency and direct data centre links to support cloud, AI and edge workloads. This presents a significant opportunity for India to build faster, more resilient digital corridors. At the same time, it raises strategic questions with regard to landing rights, data sovereignty and oversight of cable infrastructure, requiring regulators to weigh foreign investment against national control.

Rising cross-sector demand

The demand for submarine cables is now being driven by emerging technologies and long-neglected regions. Offshore wind-feeding farms and oil platforms are now equipped with high-capacity data links alongside power transmission. AI and cloud computing depend on global connectivity with low latency and high throughput, while 5G and edge computing rely on resilient links with trusted international fibre backbones. In many islands and coastal locations, submarine cables are the only available option for reliable broadband connectivity. India’s efforts to lay fibre-optic cables up to the Andaman and Nicobar Islands and the Lakshadweep Islands highlight the significant role of such infrastructure.

Innovation beyond capacity

With older systems reaching their design limits sooner than expected, new builds are prioritising higher capacity per fibre pair. Technologies such as multicore fibre, spatial division multiplexing and advanced repeaters allow operators to scale capacity without a proportional increase in physical infrastructure or cost. Beyond communications, hybrid systems capable of transmitting both power and data are becoming more common, particularly in offshore renewable energy projects.

Sustainability: a rising priority

As the race towards net zero gains urgency, every player in this digital infrastructure ecosystem is entrusted with playing a particular role and cable operators are no exception. Depending on one’s region and local environmental agency regulations, operators will likely have to conduct environmental impact assessments, track post-installation impacts and plan for end-of-life retrieval.

Financing the next frontier

The global pipeline of cable projects is growing, but translating plans into deployments, especially in emerging markets, remains challenging. Public-private partnerships offer a viable solution, as demonstrated by India’s BharatNet project. By combining government initiatives with private sector innovation and local implementation, the project has brought broadband to thousands of rural and remote areas. Such collaborations can accelerate digital inclusion while strengthening national resilience.

Looking ahead

The coming decade is expected to witness more investment in submarine cables than in the past several decades combined. But success will not be measured in kilometers alone. The new submarine cable landscape will be defined by its ability to support distributed cloud ecosystems, connect offshore energy projects to national grids, and deliver meaningful, affordable connectivity to all regions, including those historically left behind.

India’s strategic location in the Indian Ocean further reinforces its role as a regional hub for global connectivity, linking Asia, Africa and Europe. As digital infrastructure becomes increasingly strategic – economically, politically and environmentally – submarine cables are no longer just silent enablers. They are critical infrastructure for a future defined by both connectivity and sustainability. Getting this vision right requires long-term thinking, cross-sector collaboration and bold investment in the invisible systems that power our digital and low-carbon future.