Facebook and Microsoft announced a partnership today to lay the highest-capacity subsea internet cable to ever cross the Atlantic Ocean, starting with hubs connecting Northern Virginia to Bilbao, Spain. The cable, called "MAREA" after the Spanish word for "tide," will be capable of 160 terabits per second of bandwidth and will stretch more than 4,100 miles of ocean in a submarine cable system. The two companies have hired Telxius, the infrastructure company owned by global communications giant Telefónica, to manage MAREA and expand network hubs from Europe to Africa, the Middle East, and Asia. Construction is slated to begin in August of this year with a goal of October 2017 to complete the cable.

"In order to better serve our customers and provide the type of reliable and low-latency connectivity they deserve, we are continuing to invest in new and innovative ways to continuously upgrade both the Microsoft Cloud and the global internet infrastructure," Frank Rey, Microsoft's director of global network acquisition, said in a statement. "This marks an important new step in building the next generation infrastructure of the internet." Even with Telxius onboard, this new operation marks a turning point for tech companies, which have in the past joined telecom consortiums that already operate undersea cables rather than financing new cables outright.

The ultimate goal here is to help both Facebook and Microsoft move information around the world — to their vast and expanding networks of data centers — at higher speeds using more reliable equipment. Both companies now maintain massive cloud-computing operations, with Facebook hosting the output of 1.65 billion users and Microsoft managing a robust suite of online services including Azure, Bing, Xbox Live, and Office 365. To continue expanding, these types of companies are increasingly moving into the infrastructure business, whether that be Amazon with its shipping network or Facebook and Microsoft with data operations to reach other parts of the globe.

Investing in subsea cables is not a new trend. Tech companies have been making sizable investments in global networking infrastructure for years, starting with server farms and data centers and onward to large-scale underwater operations. Although this new deal involves only Facebook and Microsoft, Google has invested in two undersea cables that stretch from the US to Japan, South America, and other parts of Asia.

Microsoft says its new project with Facebook provides interoperability with other networking equipment. "This new 'open' design brings significant benefits for customers: lower costs and easier equipment upgrades which leads to faster growth in bandwidth rates since the system can evolve at the pace of optical technology innovation," the company said in a statement.

Starry: high-speed Internet without the cables