Meta has said it will be connecting a petabit subsea cable between the US and France by 2029. Called Petal, the subsea cable will span over 4,300 miles, and, according to Meta, double the capacity of today’s most transoceanic cables.
Meta has been collaborating on the buildout of subsea network capacity with Marea in 2018, which used eight fibre pairs providing 192 tbps (terabits per second). In 2023, this was expanded to 24 fibre pairs in the 384 tbps in the Amitié cable system, where Meta worked with Microsoft, Aqua Comms and Vodafone (through Cable & Wireless Americas Systems) to connect Lynn Cable Landing Station in Massachusetts to the UK’s Bude Cable Landing Station and Le Porge Cable Landing Station in France.
In 2024, Meta launched Anjana, its first wholly owned transatlantic submarine cable system, based on 24 fibre pairs that connect Myrtle Beach (South Carolina, US) with Santander in Spain, providing 500 tbps connectivity.
With Petal, Meta said it has opted for 2-core fibre technology in a 24 fibre-pair system, equivalent to 48 fibre pairs, to make the leap to 1 pbps at transatlantic distances. The 2-core cabling means that there are two independent optical cores in each 125μm glass fibre cable.
The company has worked with NEC, Sumitomo Electric Industries and Orange to overcome the physical hurdles needed to deliver Petal. Eduardo Mateo, chief strategy officer of the submarine network division at NEC Corporation, said: “Achieving petabit-per-second capacity across a transoceanic submarine system represents a major technological milestone in the history of global telecommunications.”
Among the challenges is how to avoid crosstalk, which is interference in the transmission of light sent down the optical cabling that has an adverse affect on network speed. Sumitomo Electric Industries, NEC’s fibre supplier, developed and manufactured the 2-core fibre. According to Meta, the Sumitomo Electric Industries cabling delivers ultra-low losses and practically immeasurable crosstalk for counter-propagating signals, which it said means the cable can deliver optical performance nearly identical to single-core fibre.
Given that a 4,300-mile subsea cable needs about a hundred repeaters to amplify the digital signals along its length, Meta said Petal uses a single-body 96 amp repeater using single-core fibre amplification. This amplifier provides a fan-in/fan-out interface to transition 2-core fibre into two single-core fibres in each repeater and then back to 2-core fibre following amplification.
Orange is working with Meta on plans to land Petal ashore France’s Atlantic coast. The work includes terrestrial interconnection into the European network.
Commenting on the collaboration, Jean-Louis Le Roux, executive vice-president of Orange International Networks, said: “Reaching one petabit on a transatlantic link, 25 years after the terabit milestone, represents a significant breakthrough to meet the exponential traffic growth while optimising network capacity. This makes us very proud to welcome this new generation petabit subsea cable with dual-core fibre technology in our infrastructure, as the landing party in France.
“This new project reinforces our commitment with Meta and demonstrates our leading expertise in landing subsea systems, and extending connectivity to other European countries. It underlines our dedication to developing reliable infrastructure that guarantees the security and resilience of the terrestrial segment of those connections.”
