Facebook and Instagram's parent company, Meta, has announced plans to lay an undersea cable stretching across five continents to carry data, including for the development of artificial intelligence.

The cable will span more than 50,000 kilometers (31,000 miles) between the US, South Africa, India, Brazil, and "other regions," Meta said in a blog post on Friday.

Global digital communication relies on a vast network of undersea conduits, with roughly 1.2 million kilometers of cable already installed, according to a 2024 report by the US-based Center for Strategic and International Studies (CSIS).

The links can range from short hops between countries to globe-spanning systems linking multiple continents. Each cable is made up of multiple pairs of fiber-optic cables in an armored sheath, which may be buried several meters under the sea bed for protection.

Data-hungry digital giants like Meta have recently entered the subsea cable world, a domain once controlled by dedicated telecom providers.

"At some point, when your growth is so big and your demand volumes outweigh others, you're incentivized to invest yourself and cut out the middleman," said Alan Mauldin, research director at specialist data firm Telegeography.

Meta said its latest cable project represents a "multi-billion-dollar, multi-year investment" — a relative drop in the bucket compared to the sector's tens of billions annually in planned artificial intelligence investments.

Resilient networks

Google and Meta's efforts, whether by joining cable-building consortiums to part-own new infrastructure or going it alone, have been particularly intensive given the vast appetite for data on their platforms like YouTube, Facebook, and Instagram.

The new "Project Waterworth" cable will be Meta's third as a sole owner, according to Telegeography's listings — well behind Google, which owns 16.

Meta's first cable, "Anjana," linking the US and Spain, is set to come online early this year.

"Waterworth" is named after a late Meta employee, Gary Waterworth, who worked for five years at the US tech giant after a career largely spent at Alcatel Submarine Networks (ASN).

The French cable-laying firm is one of only a few worldwide capable of installing the hardware, alongside America’s SubCom, Japan’s NEC, and China’s HMN.

Platforms' motives for getting into the cable game also include directly linking their global operations and increasing their networks’ resilience, Mauldin said.

"One new big, high-capacity cable doesn’t do you any good... you need to have three or four because if one goes down, or two go down, you can still route the traffic," he noted.

Every year, around 200 incidents of cable damage occur that could otherwise endanger vast swaths of economic activity. These incidents can stem from natural causes like underwater landslides and tsunamis, or human causes like dragging ship anchors or fishing equipment.

AI stoking data traffic

Cables can also be targets for deliberate sabotage and spying.

In January, NATO launched dedicated patrols of the Baltic Sea after suspected attacks on telecom and power cables that experts and politicians have blamed on Russia.

Meta's "Waterworth" route avoids geopolitical hotspots like the South China Sea, which is subject to dispute between Beijing and its neighbors, and the Red Sea, Mauldin pointed out.

The company also said the cable project would provide "the abundant, high-speed connectivity needed to drive AI innovation."

"AI is the hottest issue in the industry right now," Mauldin said, though its impact on demand for cables and bandwidth remains unclear.

"Training" new AI models could require transmitting large amounts of data quickly to computing clusters around the globe, he noted, while AI inference — its actual responses to users' prompts — will also have transmission requirements.

"A lot of companies could be emerging in this space, but the big companies, the big hyperscalers, seem to have a really big advantage with existing data centers and networks," Mauldin said.

He pointed to examples such as OpenAI — backed heavily by Microsoft, another player with stakes in undersea cables — and Anthropic, supported by Google and Amazon.