Mint Explainer | What makes undersea cables vital to your internet

But what happens when this backbone takes a hit? On Saturday, cable cuts in the Red Sea, a critical route for both global trade and communications, disrupted internet access in parts of Asia and West Asia.

Mint breaks down what undersea cable cuts mean for your internet, how and why they happen, how long repairs take, why the Red Sea is a strategic hotspot, and how telecom companies and technology giants are affected.

Why are undersea cables important?

Undersea cables are like giant internet wires lying on the ocean floor. They connect countries and carry huge amounts of data—including calls, messages, and videos—between continents in seconds. Subsea cables are also important for global financial transactions as well as artificial intelligence-related advancements.

If you’re watching a YouTube video from the US while sitting in India, the video would have traveled across continents through this network of undersea cables. Once data related to the video reaches India, it travels through land cables to cell towers or Wi-Fi routers. From there, it reaches your phone or computer.

According to Broadband India Forum (BIF), which represents big tech companies such as Meta and Alphabet that have heavily invested in laying subsea cables, there are 559 such active cables across the world. These cables can carry 16,000 terabits per second (tbps), enough to stream millions of HD videos, transmit billions of WhatsApp messages, or support huge cloud services, all at the same time.

India has 17 subsea cables, which is 3% of the global total, BIF said at an industry event in March. Alphabet, Meta, Bharti Airtel Ltd, and Reliance Jio are working on laying more such cables.

India’s communications ministry in a statement in December estimated 150-200 faults in subsea cables globally every year.

What happens when these cables get cut?

Subsea cables can be cut by ships dragging their anchors, fishing nets getting entangled with them, or natural events like earthquakes or underwater landslides. However, there’s growing concern about intentional sabotage, where cables are deliberately cut to disrupt internet connectivity, especially in sensitive regions like the Red Sea.

Accidental or intentional, undersea cable cuts cause loss of communication or reduced internet speeds, affecting both enterprises and common users. According to BIF, recent incidents in the Red Sea and South China Sea caused major disruptions affecting 25% of data traffic between Asia and Europe.

On 7 September, global internet monitoring agency NetBlocks reported a series of subsea cable outages in the Red Sea, resulting in degraded internet connectivity in India and other countries.

The outage was reportedly due to cuts in two cable systems—the South East Asia-Middle East-Western Europe 4 cable, operated by Tata Communications Ltd; and the India-Middle East-Western Europe cable, run by a consortium that counts Airtel and Tata Communications as members.

What can companies do when subsea cables are affected?

Microsoft said on Saturday after undersea cables in the Red Sea were cut that clients of its Azure cloud platform might experience increased latency.

When such disruptions happen, telecom operators, internet service providers and other such firms usually route data traffic via other cables to ensure connectivity is maintained. But with increasing data demand and rising traffic, it is crucial to expand the undersea cable network.

“There are multiple cables that come into the country. The outages in some of these cables do impact consumers as the speeds go down but companies have policies to route the traffic to multiple cables who have capacities to cater the traffic,” said Amajit Gupta, group chief executive and managing director at network infrastructure provider Lightstorm Telecom Connectivity Pvt. Ltd.

“The way GCC (global capability centre) is functioning, there are companies that work interconnected across the world, and employees sitting in India are working on virtual machines hosted in a cloud somewhere. But if a submarine cable has an outage for even a minute or the latency increases, you’re talking about 5,000-6,000 employees in an office working in a delayed or slow manner,” Gupta said.

Global capability centres are offshore units of multinational companies in countries like India that handle critical technical and other tasks.

How long does it take to repair such cuts?

According to industry executives, repairs usually take between a few weeks to several months. This is because there are no indigenous cable repair vessels or depots available in India, leaving the country dependent on marine service providers from Singapore and Dubai for subsea cable repairs along its coastline.

“India is dependent upon two service providers, namely (Dubai-based) E-marine and SEAIOCMA (South East Asia and Indian Ocean Cable Maintenance Agreement), with repair times averaging between 3-5 months,” said the Broadband India Forum.

Repair costs are high also due to cumbersome customs clearance and multiple permits and clearances required for repair ships, according to industry experts.

Why is the Red Sea key for undersea cables and issues around it?

The Red Sea is crucial for undersea cables because it serves as a key global hub connecting Europe, Asia, and Africa. According to the Observer Research Foundation (ORF), the Red Sea hosts more than 15 subsea cables connecting Europe and Asia. These cables carry 80% of Asia’s westward traffic, it said. Globally, that is 17% of the data traffic.

Geopolitical factors in the Red Sea, including attacks by Houthi rebels on ships and undersea cables, have also resulted in disruptions. Lately, operators are looking at considering land-based routes to avoid these disruptions.

What does the industry want from the Indian government?

The industry is seeking regulations allowing for greater ease of doing business, including a single-window clearance for deploying, repairing, and maintaining subsea cables, and for setting up indigenous subsea cable repair ships and facilities. Currently, about 60 ships globally cater to more than 100 countries, according to the Broadband India Forum.

The industry also wants the government to reduce the licence fees for operators of subsea cables in India. In June 2023, the Telecom Regulatory Authority of India sent its recommendations to the department of telecommunications on a licensing framework and regulatory mechanism for submarine cable landing in India.