Underwater cables are a vital piece of the AI buildout and internet — investment is booming

Over 95% of planetary information and dependable telephone postulation travels done astir a cardinal miles of underwater connection cables.

These cables transportation authorities communications, fiscal transactions, email, video calls and streaming astir the world.

The archetypal commercialized telecommunication subsea cablegram was utilized for telegraphs and was laid crossed the English Channel betwixt Dover, England and Calais, France successful 1850.

The exertion past evolved to coaxial cables that carried telephone conversations, and astir recently, fibre optics that ferry information and the net arsenic we cognize it.

"About 10 years ago, we saw the advent of different large category, which is the webscale players and the likes of Meta, Google, Amazon, etc., who correspond present astir apt 50% of the wide market," said Paul Gabla, main income serviceman astatine Alcatel Submarine Networks.

Alcatel is the world's largest subsea cablegram shaper and installer, according to manufacture commercialized mag Submarine Telecoms Forum.

Demand for subsea cables is expanding arsenic tech giants contention to make computation-intensive artificial intelligence models and link their increasing networks of information centers.

Investment into caller subsea cablegram projects is expected to scope astir $13 cardinal betwixt 2025-2027, astir doubly the magnitude that was invested betwixt 2022 and 2024, according to telecommunications information supplier steadfast TeleGeography.

"AI is expanding the request that we person for subsea infrastructure," said Alex Aime, vice president of web investments astatine Meta. "Oftentimes erstwhile radical deliberation astir AI, they deliberation astir information centers, they deliberation astir compute, they deliberation astir data. But the world is, without the connectivity that connects those information centers, what you person are truly costly warehouses."

In February, the institution announced Project Waterworth, a 50,000km (31,000-mile) cablegram that volition link 5 continents, making it the world's longest subsea cablegram project.

Meta volition beryllium the sole proprietor of Waterworth, which the institution says volition beryllium a multi-year, multi-billion-dollar project.

Amazon besides precocious announced its archetypal wholly-owned subsea cable task called Fastnet.

Fastnet volition link Maryland's eastbound enactment to County Cork, Ireland, and capableness volition transcend 320 terabits per second, which is equivalent to streaming 12.5 cardinal HD movies simultaneously, according to Amazon.

"Subsea is truly indispensable for AWS and for immoderate connectivity internationally crossed oceans," Matt Rehder, Amazon Web Services vice president of halfway networking, told CNBC successful an interrogation astir Amazon's subsea cablegram investments. "Without subsea you'd person to trust connected outer connectivity, which tin work. But outer has higher latency, higher costs, and you conscionable can't get capable capableness oregon throughput to what our customers and the net successful wide needs."

Google is different ample player, having invested successful implicit 30 subsea cables.

One of the company's latest projects is Sol, which volition link the U.S., Bermuda, the Azores and Spain.

Microsoft has besides invested successful the infrastructure.

"You've seen this immense maturation successful submarine cables implicit the past 20 years. And this is driven by conscionable a voracious request for data," says Matthew Mooney, manager of planetary issues astatine cybersecurity steadfast Recorded Future.

Disruptions owed to cablegram harm tin beryllium rather significant, peculiarly successful areas served by fewer net connections.

"If you chopped a cable, you tin chopped disconnected aggregate countries from net access, and that includes fiscal transactions, banking, e-commerce and basal communications," said Erin Murphy, a elder chap astatine the Center for Strategic and International Studies, a nonprofit nationalist information probe organization.

That precise happening happened to Tonga, an land federation eastbound of Australia.

In 2022, debris from an underwater volcanic eruption severed the island's lone subsea connection cable, cutting the land disconnected from the remainder of the world.

In September, cuts to subsea cables successful the Red Sea caused disruptions to Microsoft's Azure unreality service. The institution was capable to re-route traffic, but users successful Asia and the Middle East inactive faced accrued latency problems and degraded performance.

Experts person said that the bulk of subsea cablegram harm is accidental, usually owed to sportfishing enactment oregon a vessel accidentally dropping its anchor connected a cable. But lately, these cables are becoming the suspected targets of sabotage.

"When you person truthful galore vessels successful planetary waters that are highly trafficked by tons of commercialized vessels oregon sportfishing vessels, the likelihood of accidents is reasonably high," Murphy said. "But if you're a hostile actor, you cognize that arsenic well. So if you're sending retired the alleged Russian shade fleet, oregon if you person a Chinese sportfishing vas and a cablegram is accidentally cut, you could conscionable say, 'Oh, well, it was an accident.' But it could beryllium intentional. So it's truly hard to discern sometimes erstwhile an enactment of harm is really intentional oregon accidental."

Mooney and Recorded Future person been tracking immoderate of these cases of suspected sabotage.

"I would accidental that we person seen a important uptick successful what we would see intentional damages," Mooney said. "In 2024 and 2025, [we] saw a notable summation successful incidents that occurred successful the Baltic Sea and astir Taiwan. And truthful it is hard to beryllium capable to find with 100% validity that these are intentional. However, the information patterns that look from these events does springiness you origin to beryllium suspicious that they could each beryllium considered accidental."

Mooney said the summation successful suspected sabotage has corresponded to accrued tensions betwixt Russia and Ukraine and China and Taiwan.

Despite determination being a deficiency of factual grounds of subsea cablegram sabotage, governments are taking the menace seriously.

In January, NATO launched the "Baltic Sentry" following respective incidents of cablegram cuts successful the Baltic Sea. The cognition involves deploying drones, craft and subsea and aboveground vessels to safeguard the subsea infrastructure successful the region.

"As a result, I don't judge we've seen immoderate instances of cablegram severing since precocious January 2025, successful the Baltic Sea," Mooney said.

In the United States, the Federal Communications Commission, which is liable for granting licenses to anyone wishing to instal oregon run subsea cables connecting to the U.S., has introduced tighter rules connected overseas firms gathering this infrastructure, citing information concerns.

"One country we've been peculiarly focused connected are threats that travel from the Chinese Communist Party arsenic good arsenic from Russia," FCC Chair Brendan Carr told CNBC. "So we're taking actions close present to marque it hard oregon efficaciously prohibiting the quality to link undersea cables straight from the U.S. to a overseas adversary nation."

Carr said the FCC is besides taking steps to marque definite the hardware itself isn't compromised, not allowing Huawei, ZTE oregon different questionable "spy gear" to beryllium utilized successful undersea cables.

In July, 3 House Republicans sent a letter to the CEOs of Meta, Amazon, Google and Microsoft asking if the companies person utilized PRC-affiliated cablegram attraction providers.

In effect to CNBC's question astir the letter, Meta's Aime said, "We bash not enactment with immoderate Chinese providers of cablegram systems connected systems that we've announced, and we are successful afloat compliance with U.S. argumentation regulations astir partners successful the ecosystem and the proviso chain."

Amazon besides told CNBC it does not enactment with Chinese companies.

Microsoft and Google did not instrumentality CNBC's petition for remark connected the letter.

To recognize however subsea cables work, CNBC visited Alcatel Submarine Networks subsea cablegram manufacturing facilities successful Calais, France and Greenwich, England. We besides spoke to authorities officials and tech giants to find retired wherefore subsea cables are important to keeping america connected and what we tin bash to support this captious infrastructure.

Watch the video to get the afloat story.