Indian Council of World Affairs

On September 7, 2025, several submarine communication cables (sub-cables/submarine cables) in the Red Sea were severed, causing significant internet outages across some regions of the Middle East and Asia^[i]. NetBlocks, a watchdog that monitors internet governance, reported that the damage impacted major subsea systems, specifically the South-East Asia–Middle East–Western Europe 4 (SMW4) and the India-Middle East-Western Europe (IMEWE) lines caused by a vessel. 

This episode warrants revisiting submarine cables, why they are important, their changing landscape, and how geopolitics is being practiced through sub-cables with focus on US-China rivalry. This special report aims to discuss submarine cables, the tech behind them, their evolving complex landscape and the geopolitics.

The Data Speaks through Me: Sub-cables and the Tech Behind

From watching Friends (an American sitcom) on Netflix in India, to a foreigner using a credit card in London, or participating in multiplayer online gaming and international video calls etc, have you ever wondered what makes all of this possible?  It seems as if there exists an imaginary super-highway with countless lanes through which our data travels simultaneously. These super-highways form the backbone of the internet and modern communication systems referred to as the submarine cables. These cables handle nearly all of the world’s international internet traffic, over 95%, while satellites transmit only a small fraction of it ^[ii]. These cables can transmit multiple terabits of data per second, facilitating fastest and most reliable means of global data transmission. For example, a single cable can carry data belonging to millions of people.

It all started in Britain when the successful laying of telegraph lines done on land, paved the way for undersea communications. And in 1800’s when an American-British venture successfully laid the cables across the Atlantic Ocean, it led to formal exchange of congratulatory message between US President James Buchanan and Queen Victoria hailed by a newspaper as the moment where “the Old and New Worlds are brought into instantaneous communication”.^[iii] Over time, the copper cables were replaced by fibre optic^[iv] cables as they were more efficient and offered more speedy transfer of data globally.

Today data in the form of video messages, photos, voice messages, emails etc, is converted into binary code (1s and 0s). For instance, when someone searches information online like about the protest in Nepal, a radio signal travels from the person’s device to a nearby mobile tower on land. From there, the signal converts into pulses of light^[v] and sent via cables to distant servers (data centres) located in some far-off locations like U.S. These servers then retrieve the data, break it into small data packets (smaller bits of data in binary code), and sends it back through the same optical route through pulses and the person gets the required information.[vi] These cables go all the way down to the ocean floor. Near coastlines, they’re buried under the seabed to keep them protected, but in the deep sea they are just laid alongside the seabed itself.

 
Figure 1 Parts of Submarine Cable, Telegeography 

The Changing landscape of the Undersea Empire

Figure 2 Present Map of Submarine Cables

By looking at the map of these cables their geographic location is revealed which helps in identifying which countries, companies, and commercial hubs that command & control this critical digital infrastructure. According to the Hinrich Foundation study, the most densely packed clusters of cables originate and terminate between the United States (US) and Europe, and these same places have major arterials connecting to economic hubs in Asia, namely Japan, China, Taiwan, and about a dozen other places.^[vii] All the data including financial, critical military, government data etc flows through these clusters. Fewer than a dozen countries possess the advanced capabilities to design, deploy, and operate undersea cable networks which include the United States, several key European allies, Japan, South Korea, China, and Russia (to a lesser extent).^[viii]

Primarily, submarine cables are laid by private companies called ‘cable-operators’, with the maintenance handled separately by private companies which operate via specially designed ships crewed by highly skilled technicians.^[ix] The maintenance of submarine cables is carried out through either a ‘Club Agreement’^[x] or ‘Private Maintenance Agreement^[xi]’.^[xii] Approximately 98 percent of the world’s submarine cables are built, owned, installed, operated and maintained by four private firms: American SubCom, French Alcatel Submarine Networks, Japanese Nippon Electric Company, and now Chinese HMN Technologies, (formerly known as Huawei Marine Networks Co., Ltd)^[xiii]. Commercial submarine cables are typically owned either by a single entity or, more commonly, by a consortium of companies. Ownership spans across telecommunications firms, content platforms like Meta (formerly Facebook), and major cloud service providers such as Google, Microsoft, and Amazon.^[xiv]

The submarine cable landscape is undergoing a significant transformation, characterized by shifts in ownership, a rapid expansion of strategic cable routes, high-capacity cable deployments in the form of mega projects, changes in geographic distribution, etc. The Ownership is shifting from the traditional telecom companies and government backed consortium to Hyperscalars i.e., large cloud and content service providers such as Google, Meta, Microsoft and Amazon.^[xv] Historically, submarine cables were owned by telecommunications carriers operating through consortiums that pooled investment and shared capacity but in the late 1990s, private firms began constructing their own cables and selling capacity directly to users[xvi]. Since the early 2010s, increased bandwidth demand has led content providers to transition from purchasing wholesale capacity to owning and managing global transport infrastructure. Currently, both ownership models are present in the market, but it has changed significantly with the involvement of major content providers such as Google, Meta, Microsoft, and Amazon and these companies represent most new cable investments.[xvii] The four companies (Google, Meta, Microsoft and Amazon) have grown from less than 10% to an exponential rise to 71% ownership in just a decade.^[xviii]  

Also, a more visible finding is that HMN, a Chinese telecommunications research firm though accounted for only about 10% of global market share for subsea construction spending in 2023, but it grew faster than any of its competitors from 2008 to 2023.^[xix] Moreover, a notable finding in the global undersea cable landscape is the overreliance on Chinese repair capabilities repair which is an important part of the submarine infrastructure as the repair industry requires highly trained crew and sophisticated vessels. China remains the fourth-largest player in the cable construction along with the repair industry and Chinese firm HMN Technologies has been involved in nearly 25% of existing subsea cable construction or repairs highlighting underscoring its growing strategic relevance.^[xx]

Further, the process of constructing and laying the submarine cables have fastened over the years. The chart below shows that the launch of submarine cable has increased rapidly since 2020 and will continue to rise due to increasing global data traffic, laying in underserved regions as avenues for new markets, and the need to ensure network resilience through route redundancy.^[xxi] The total number of submarine cables has grown significantly since 2010, with accelerated deployment from 2020 onwards as shown in the figure below.^[xxii]

A visible trend has emerged in the expansion of submarine cable projects into new and increasingly contested geographic regions for example the launch figures in developed Asia–Pacific increased rapidly, from 21 in 2020 to 33 in 2023, while those in emerging Asia–Pacific increased from 26 to 38. According to Analysys Mason between 2010 and 2023, Western Europe saw the highest number of new submarine cable launches, totalling 77 followed by Emerging Asia–Pacific with 71 new cables, developed Asia–Pacific having 68[xxiii]. Other regions included North America with 45, the Middle East and North Africa with 44, Sub-Saharan Africa with 30, Latin America with 28, and Central and Eastern Europe with 7 new cables. The data and the ready for service map (below) shows that the most planned/in deployment cables can be found in developed and emerging Asia–Pacific region. 

Figure 4 Prepared by the Researcher with the help of Co-Pilot

The 2025 Ready for Service Sub-Cables Map

Source: Submarine Cables

Also, the recently announced sub-cable projects are mega projects in nature and are becoming a tool of influence. For example, Meta’s Project Waterworth, a 50,000-kilometer cable network stands out as the first of its scale to be privately owned by just one company i.e., Meta. It will be the longest in the world longer than the Earth’s circumference and will connect the US, India, South Africa, Brazil along with other regions. This marks a fundamental shift as these corporations not only dominate digital platforms, but they also increasingly control the physical foundations of the internet itself.^[xxiv] Also, the 2Africa cable stretching approximately 45,000 kilometres and will connect 33 countries across emerging regions in Asia–Pacific, the Middle East and North Africa, Sub-Saharan Africa, and Western Europe. Meanwhile, the Bifrost cable is an open cable system that will span over 15,000 kilometers, connecting the United States, Singapore, Guam, Indonesia, Mexico, and the Philippines. Another significant project, the Echo cable, jointly owned by Google and Meta will connect the United States with Singapore, Guam, Indonesia, and Palau, reinforcing digital infrastructure between Southeast Asia and North America.

This transition to cable ownership by Hyperscalars has given them the decisions making power regarding the location of cables, reshaping the architecture of the global cable network. These tech giants or Hyperscalars now have access to large data including massive critical, sensitive and private data. In the future this dominance may result in setting the terms of access and create barriers to entry of small players especially from the Global South. The strategic interests and decisions of private corporations may influence the security of the states.

Geopolitical Practices through Sub-cables with the focus on US-China rivalry

Geopolitics is primarily understood through grand strategy and great power politics (like military pacts diplomatic summits, strategic doctrines, foreign policy etc). But as John Agnew, a renowned geographer says one needs to see the actual working of geopolitics i.e., how geopolitics is actually practiced and experienced, it builds that gap between theory and action.[xxv] The geopolitical practices of submarine cables manifest global politics through security narratives, materiality, grey-zone tactics, institutional signalling, etc. In this paper, submarine cables are viewed as emerging active sites where geopolitics is actively performed and experienced especially in the context of US-China rivalry.[xxvi]

The most visibility of geopolitics is seen in the way states are indirectly colluding with corporates to own and lay these cables. US based Hyperscalars like Meta, Google, Amazon, Microsoft and similar companies have emerged as key geopolitical players in the construction, leasing, laying, operating most of these cables. The mega projects like Meta’s Waterworth, Meta and Google’s trans-pacific Echo and Bifrost, Google’s Equiano connect Africa with Europe etc.[xxvii]  Under Chinese government’s Digital Belt and Silk Road, Chinese tech corporation previously called Huawei now HMN Technologies is at the forefront of expanding the construction of undersea cable networks in the Indo-Pacific for instance China now has a permanent access to undersea cable landing stations across the Indo-Pacific through the Pakistan and East Africa Connecting Europe (PEACE) cable, valued at US$425 million. According to a report by the International Institute of Strategic Studies (IISS) claims Beijing to have completed 11 undersea cable projects in Indonesia, seven in South Korea and six in the United Arab Emirates.[xxviii] The United States is prioritizing landings in politically secure and geopolitically aligned regions, such as Guam, Japan and Australia, while China through BRI is expanding its influence in Southeast Asia, Africa, and the South Pacific.

Again, the tactics which occur during peace time i.e., the grey-zone tactics (deniable attacks short of war) signals how undersea cable disruptions are increasingly used as tools of geopolitical coercion on a daily basis. For instance, in Taiwan’s Matsu Islands, suspected Chinese vessels had cut cables, leaving 14,000 residents offline for six weeks, part of what Taipei calls Beijing’s “grey-zone aggression,” with 27 such incidents since 2018. [xxix] In the Baltic Sea, telecom and gas infrastructure linking Finland, Estonia, and Sweden were damaged in 2023, with investigators pointing to a Russian-flagged vessel and a Chinese ship, The New Polar Bear, behind the incident. Following the Grey zone tactics, states create narratives of threats to national security through submarine cables.[xxx] These Grey zone incidents (which are deniable and non-attributable) are used by the states such as US in this case, to build and justify the whole narrative of securitization of cables vis-a-vis China.[xxxi] For example, U.S. lawmakers called upon major US tech companies such as Alphabet, Meta, Amazon, and Microsoft about the national security concerns in questioning the safety of submarine communication cables, showcasing how discourse translates into securitization.[xxxii]

The US discourse on submarine cables often positions Chinese companies as carrying out cyber espionage and surveillance through its digital silk road initiative[xxxiii]. China portrays US as hegemonic.[xxxiv] These discourses are actively shaping international norms, influencing investment decisions, and justifying the rerouting and diversification of cables. Further, the institutional aligning through rules and regulations also plays an important role in Geopolitics of cables. Like for instance, in 2021, Google and Meta were party to a national security agreement with the US Department of Justice that allowed the Pacific Light Cable Network (PLCN) to proceed, only after they agreed to exclude their Chinese partner and diversify landing points to countries such as Indonesia, Vietnam, and the Philippines.[xxxv] China has made it mandatory to have a permit, enabling Chinese authorities to reinforce its sovereignty especially in South China sea.[xxxvi]

Critical Reflections

As sociologist Manuel Castels has rightly put, that today we live in a networked society and in this networked society, 95 percent of the entire global data flows through sub-cables, therefore it is important to understand these submarine cables. Through this report, light has been shed on what are these cables, what is the tech behind them, why they are important and how a change is being witnessed in the sub-cable landscape. From new geographic locations to new ownership to nature of the submarine projects to the geopolitics of these cables, a lot has been changing in and through submarine cables. The report uses submarine cables as a lens to reveal the often-neglected practices through which states enact geopolitics that are frequently overshadowed by meta theories and foreign policy discourse. The report tells us the importance of caution in building narratives & theories about things which have become part of our daily lives across the globe and linking them to geopolitics shows how submarine cables have become active sites of everyday geopolitics engagement through ordinary everyday framing of national security narrative, regulatory decisions, material developments, and institutional signalling. Subsea cables make visible how powers like the U.S. and China perform and carry out geopolitics through routine practices. It is not just the grand military strategy or foreign policies or strategic posturing w.r.t submarine cables but the everyday national security narratives, materiality, Grey-zone tactics, institutional signalling etc actively performed and experienced especially in the context of US-China rivalry through cables.

*****

*Anubha Gupta, Research Associate, Indian Council of World Affairs, New Delhi.
Disclaimer: Views expressed are personal.

Endnotes

[i] Deep, A. (2025, September 8). Indian networks face higher ‘latency’ to Europe following Red Sea cable cuts. The Hindu. https://www.thehindu.com/incoming/indian-networks-face-higher-latency-to-europe-following-red-sea-cable-cuts/article70026779.ece   (Accessed September 8, 2025)

[ii] Chataut, R. (2024, April 1). Submarine cables are the unseen backbone of the global internet. The Conversation. https://theconversation.com/undersea-cables-are-the-unseen-backbone-of-the-global-internet-226300 (Accessed September 22, 2025)

[iii] Singh, R. (2025, September 9). Red Sea cable cut interrupts internet in Asia: How data travels to you under the ocean. The Indian Express. https://indianexpress.com/article/explained/explained-sci-tech/undersea-cables-red-sea-internet-working-simplified-10239041/ (Accessed September 22, 2025)

[iv] Fiber-optic cables use hair-thin glass or plastic strands to transmit data through total internal reflection, allowing light signals to travel long distances with minimal loss. Optical repeaters placed along the seabed amplify weakened signals, enabling high-speed data transfer across oceans.

[v] Radio waves received at a tower are converted into electrical signals, which a laser or LED then turns into pulses of light for transmission through optical fibers. At the other end, photodetectors reverse the process, restoring the signal for delivery to the user’s device.

[vi] HowStuffWorks. (2000, June 15). How does a fiber optic cable work? HowStuffWorks. https://electronics.howstuffworks.com/question402.htm

[vii] Capri, A. (2024, April). The new geopolitics of submarine cables. Hinrich Foundation. https://research.hinrichfoundation.com/hubfs/White%20Paper%20PDFs/The%20new%20geopolitics%20of%20undersea%20cables%20%28Alex%20Capri%29/The%20New%20Geopolitics%20of%20Undersea%20Cables%20-%20Hinrich%20Foundation%20-%20Alex%20Capri%20-%20April%202024.pdf (Accessed September 22, 2025)

[viii] Ibid.

[ix] Runde, D. F., Murphy, E. L., & Bryja, T. (2024, August 16). Safeguarding subsea cables: Protecting cyber infrastructure amid great power competition [Report]. Center for Strategic & International Studies. https://www.csis.org/analysis/safeguarding-subsea-cables-protecting-cyber-infrastructure-amid-great-power-competition (Accessed September 22, 2025)

[x] Club Agreement, cable operators form a consortium and share maintenance costs.

[xi] Private Maintenance Agreements are bilateral agreements between cable operators and maintenance ship owners.

[xii] Ibid.

[xiii] Calabrese, J. (2025, April 10). China’s new underwater tool cuts deep, exposing vulnerability of vital network of subsea cables. The Conversation. https://theconversation.com/chinas-new-underwater-tool-cuts-deep-exposing-vulnerability-of-vital-network-of-subsea-cables-251877 (Accessed September 18, 2025)

[xiv] Congressional Research Service. (2024, December 13). Protection of undersea telecommunication cables: Issues for Congress (CRS Product No. R47648). Library of Congress. https://www.congress.gov/crs-product/R47648(Accessed September 18, 2025)

[xv] PYMNTS. (2024, October 1). Big Tech’s undersea cable empire is building tomorrow’s digital economy. PYMNTS. https://www.pymnts.com/connectedeconomy/2024/big-techs-undersea-cable-empire-is-building-tomorrows-digital-econom  (Accessed September 18, 2025)

[xvi] https://www2.telegeography.com/submarine-cable-faqs-frequently-asked-questions

[xvii] https://blog.telegeography.com/telegeography-content-providers-submarine-cable-holdings-list-new

[xviii] Kang, J., & Jacob, J. (2024, September). Connecting the Indo-Pacific: The future of subsea cables and opportunities for Australia [Policy brief]. Australian Strategic Policy Institute. https://ad-aspi.s3.ap-southeast-2.amazonaws.com/2024-09/Connecting%20the%20Indo-Pacific%20-%20The%20future%20of%20subsea%20cables%20and%20opportunities%20for%20Australia_0.pdf?VersionId=.LcTT0ZYi0Nab6DeTCLgQ8M1a15m42nD (Accessed September 18, 2025)

[xix] Library of Congress, Congressional Research Service. (2023). Undersea Telecommunication Cables: Technology Overview and Issues for Congress (CRS Report No. R47237). Retrieved from https://www.congress.gov/crs-product/R47237/ (Accessed September 18, 2025)

[xx] Ibid.

[xxi]Analysys Mason. (2025, May 10). Submarine cable launches. Retrieved September 22, 2025, from https://www.analysysmason.com/research/content/articles/submarine-cable-launches-rma22-rdfi0 (Accessed September 15, 2025)

[xxii]Ibid.

[xxiii] Ibid.

[xxiv] Badshah, N. (2025, February 17). Meta plans to link US and India with world’s longest undersea cable project. The Guardian. https://www.theguardian.com/technology/2025/feb/17/meta-plans-to-build-worlds-longest-underwater-sub-sea-cable-venture (Accessed September 12, 2025)

[xxv] Agnew, J. (1994). The territorial trap: The geographical assumptions of international relations theory. Review of International Political Economy, 1(1), 53–80. https://doi.org/10.1080/09692299408434268

[xxvi][xxvi] Goede, Marieke & Westermeier, Carola. (2022). Infrastructural Geopolitics. International Studies Quarterly. 66. 10.1093/isq/sqac033. (Accessed September 12, 2025)

[xxvii] Lehdonvirta, V., & Mikelsaar, A. (2025, March 10). What Meta’s plan to build the world’s longest undersea cable means for digital infrastructure and geopolitics. Oxford Internet Institute. https://www.oii.ox.ac.uk/news-events/what-metas-plan-to-build-the-worlds-longest-undersea-cable-means-for-digital-infrastructure-and-geopolitics/ (Accessed September 12, 2025)

[xxviii] Rahman, S. (2024, April 29). The cable ties to China’s Digital Silk Road. Lowy Institute. https://www.lowyinstitute.org/the-interpreter/cable-ties-china-s-digital-silk-road

[xxix] Reuters. (2025, June 13). China says Taiwan politicising cable damage issue, after ship’s captain jailed. Reuters. https://www.reuters.com/business/media-telecom/china-says-taiwan-politicising-cable-damage-issue-after-ships-captain-jailed-2025-06-13; Murphy, E. L., & Pearl, M. (2025, April 4). China’s underwater power play: The PRC’s new subsea cable-cutting ship spooks international security experts [Commentary]. Center for Strategic and International Studies. https://www.csis.org/analysis/chinas-underwater-power-play-prcs-new-subsea-cable-cutting-ship-spooks-international; Patil, S., & Gupta, P. (2024, May 21). Undersea chokepoints: The Red Sea cable disruptions. Observer Research Foundation. https://www.orfonline.org/expert-speak/undersea-chokepoints-the-red-sea-cable-disruptions (Accessed September 9, 2025)

[xxx] Ibid.

[xxxi] Buzan, B., Wæver, O., & de Wilde, J. (1998). Security: A new framework for analysis. Lynne Rienner Publisher.

[xxxii] https://www.thehindu.com/sci-tech/technology/lawmakers-want-us-tech-ceos-to-address-concerns-about-submarine-cables/article69841033.ece

[xxxiii] Browne, R. (2024, July 16). The next front in U.S.-China tech battle? Underwater cables that power the global internet. CNBC. https://www.cnbc.com/2024/07/16/next-front-in-us-china-tech-battle-is-underwater-internet-cables.html

[xxxiv] Brock, J. (2023, March 24). U.S. and China wage war beneath the waves – over internet cables. Reuters. https://www.reuters.com/investigates/special-report/us-china-tech-cables/

[xxxv] Thomas, P. A. (2025, July 22). US lawmakers question big tech over undersea cable safeguards. Network World. https://www.networkworld.com/article/4026355/us-lawmakers-question-big-tech-over-undersea-cable-safeguards.html (Accessed September10, 2025)

[xxxvi] Mastro, O. S. (2020, December 16). How China is bending the rules in the South China Sea. Lowy Institute. https://www.lowyinstitute.org/the-interpreter/how-china-bending-rules-south-china-sea (Accessed September10, 2025)