Submarine wire cables: Master the technology powering 95% of the world’s internet

08.05.2026

Most people never think about how their data moves. You send a message, join a call, upload a file and it just works. It might seem like it’s satellites, but it’s not.

Around 95% of international data is transmitted through submarine cable networks, running across ocean floors and connecting over 500 active cable systems worldwide . These are physical systems engineered, laid and repaired by specialised vessels and operators.

If you are working in maritime or planning to move into it, these systems are not separate from your world. They run through operational zones you navigate and depend on the same planning, risk awareness and coordination as shipping.

What makes them more complex is how exposed they are. Fishing activity and anchoring incidents account for 86% of subsea cable faults globally, with over 100 faults recorded each year. [TC3] Whenever something goes wrong, there is no quick fix. Often, crews deploy vessels, map fault locations precisely and carry out repairs in conditions that are often far from predictable. From the outside, it feels  instantaneous. In reality, it takes constant work to keep it that way.

What are submarine cable networks?

Submarine cable networks are insulated, high-capacity physical cables laid across the seabed, connecting one coastline to another. But what matters is how they are built and used in practice:

• They carry data as light: Optical fibres transmit data using light signals, making high-speed, long-distance communication across continents possible.
• They are built for harsh conditions: Each cable includes protective layers to handle pressure, friction and seabed movement. Closer to shore, operators add extra armouring to deal with anchors and fishing activity.
• They follow planned routes, not straight lines: Teams survey the seabed before installation. They avoid unstable areas and high-risk zones. In shallow water, crews bury cables beneath the seabed. In deeper areas, they lay them directly on the ocean floor.
• They operate as networks, not single lines: Landing stations connect submarine cables to onshore infrastructure. Multiple routes link regions, so data can move even if one section fails.
• They are designed to keep traffic moving: When faults happen, systems reroute data through other paths. Most users never notice the switch, but it depends on how well the network has been planned.

How do submarine wire cables power the global network?

Every time you open a website or send a file overseas, your data follows a physical path. It leaves your device, moves through local networks, reaches a landing station and then travels through submarine wire cables as light signals across the ocean. At the other end, another landing station connects it back to terrestrial networks. That entire journey happens in seconds.

• They carry continuous, high-volume traffic: Submarine cables do not send data in bursts. They handle constant flows, moving financial transactions, video calls, cloud services and platform traffic at the same time. This is why capacity matters. Modern systems can carry over 200 Tbps of data, supporting everything from streaming platforms to global financial transactions.
• They form the backbone of the global network: Major routes connect regions like Europe, Asia and North America through high-density cable corridors. These routes handle the majority of international data exchange. When one route slows down or fails, traffic shifts to others. This keeps services running, even during disruptions.
• They are owned and operated by a mix of players: The cable industry is no longer just the domain of telecom providers. Companies such as Google, Meta and Microsoft now invest directly in submarine cable networks to support their global infrastructure. At the same time, telecom operators and consortia continue to build and manage large parts of the network.
• They rely on precise coordination at sea: Installation vessels lay cables along surveyed routes. Maintenance vessels respond to faults, often working in difficult weather and in deep-water conditions. When a break occurs, teams identify the exact location, recover the cable from the seabed and repair it before traffic is restored.

What seems instant from the outside relies on a system that is always moving, adjusting and being maintained.

How does the submarine cable industry operate globally?

No single company runs submarine cable networks end to end. The industry works through partnerships, contracts and shared ownership.

• Projects start years before a cable is laid: Operators do not just choose a route and deploy the cable, much more goes into making it work. They study demand between regions, secure funding and agree on ownership structures. Most large systems are built by consortia. A group of telecom providers, technology companies and investors share the costs, capacity and long-term use of the cable. Large-scale systems can cost $200 million to over $500 million depending on length, route and capacity.
• Specialist vessels handle installation: Once routes are approved, installation contractors take over. Companies like SubCom, Alcatel Submarine Networks and NEC Corporation design and deploy the systems. Cable-laying vessels follow pre-surveyed paths, placing cables with high precision. In shallow areas, crews bury them beneath the seabed. In deep water, they lay them directly on the ocean floor. Some transoceanic cables stretch over 10,000 km, linking continents directly.
• Maintenance is continuous, not reactive: Faults happen every year, so operators position maintenance vessels strategically around the world. When a cable breaks, teams do not start from scratch. They already know the routes, access points and response procedures. Crews mobilise, locate the fault and carry out repairs, often under tight time pressure.
• Regulation shapes where and how cables run: Cables cross multiple jurisdictions. Operators need permits to land cables, agreements to pass through exclusive economic zones and compliance with environmental and maritime regulations. This adds another layer of coordination, especially for routes that span continents.
• Capacity is managed and sold over time: Once a cable is active, owners do not just use it. They allocate and sell capacity to telecom providers, enterprises and digital platforms. Over time, the same cable can support growing traffic demands through upgrades in transmission technology, without replacing the physical system.

What keeps this industry moving is not just the infrastructure itself, but coordination between operators, vessels, regulators and investors across regions.

How can you build a career in submarine cable networks?

You do not step into this space with only one job title. Most people enter it from adjacent areas such as maritime, engineering or operations.

Start with where you already are

If you work in shipping, offshore operations or port management, you already deal with routing, safety zones and coordination at sea. Submarine cable work builds on the same foundations, but with tighter risk controls and higher operational precision. You can find roles within:

• Marine operations and vessel coordination.
• Cable installation and maintenance projects.
• Route planning and seabed surveying.
• Regulatory and environmental compliance.

Understand how operations connect

What sets this industry apart is how closely everything links together. Vessel crews, engineers, planners and regulators depend on each other. You do not need to know everything from day one. However, you do need to understand how decisions in one area affect the rest of the operation.

Build skills that transfer across projects

Technical knowledge matters, but so does coordination. Teams look for people who can:

• Plan and manage offshore operations.
• Respond to faults and changing conditions.
• Work across international teams and regulations.
• Balance operational efficiency with environmental risk.

These are the same skills used across wider maritime operations, which makes movement into this space more accessible than it first appears.

Move towards roles with broader responsibility

As projects scale, so does the need for people who oversee operations end-to-end. This is where programmes like the MBA Maritime Operations at MLA College come in. They focus on real-world decision making, operational leadership and managing complex, global systems, all of which align with how the submarine cable industry runs in practice.

Submarine cable networks run through active maritime routes, depend on constant oversight and require the same level of planning and coordination as any offshore operation. Once you start looking at them this way, the industry becomes easier to understand. It is not separate from maritime. It builds on it. The systems that carry global data rely on people who can manage risk, respond to disruptions and keep operations moving across regions. The real work takes place in this area.

You do not need to start in submarine cable networks to build a career in them. Apply now for our MBA Maritime Operations programme to gain operational experience and then move closer to where these systems operate.

FAQs about submarine wire cables, the technology powering 95% of the world’s internet

Q1. What are submarine cable networks used for?

They carry international data traffic, including internet services, financial transactions, cloud systems and communication between countries.

Q2. How deep are submarine wire cables laid?

Cables can run from shallow coastal waters to depths of over 8,000 metres, depending on the route and seabed conditions.

Q3. What causes most submarine cable faults?

Most faults come from human activity, especially fishing and anchoring, followed by natural factors like seabed movement.

Q4. Who owns submarine cable networks?

Ownership is shared between telecom companies, technology firms and international consortia that fund and operate these systems.

Q5. Do submarine cables affect maritime operations?

Yes. They influence routing, anchoring zones and offshore activity, requiring coordination to avoid damage and ensure safe operations.