Meta's Petal: World's First Petabit Transoceanic Cable
Doubling subsea capacity with multi-core fiber between France and the US by 2029.
1Petabit capacity breakthrough
Petal will be the first transoceanic cable delivering 1 petabit per second (1,000 terabits) across 7,000 km between France and the US, doubling current capacity. The system uses innovative 2-core fiber technology in 24 fiber pairs, equivalent to 48 conventional pairs. This represents the largest single generational leap in subsea capacity, enabled by spatial division multiplexing without requiring proportionally more power or physical infrastructure.
2Multi-core fiber advantages
Sumitomo's 2-core fiber maintains standard 125μm width while achieving ultra-low loss and negligible crosstalk between cores. The design uses counter-propagating signals in synthetic silica with precisely controlled refractive indexes. This innovation allows doubling capacity within existing cable dimensions, reducing materials and carbon footprint compared to deploying two separate 0.5 Pbps systems.
3Repeater engineering feat
Petal's 96-amp repeaters use Fan-In/Fan-Out interfaces to split 2-core fibers into single-core paths for amplification before recombining. This maintains single-core amplification reliability while supporting spatial multiplexing. The system stays within existing 18kV power limits, avoiding ecosystem requalification. Approximately 100 repeaters will span the 7,000km route.
4Industry collaboration
NEC engineered the turnkey system including cable, repeaters, and powering architecture. Sumitomo developed the specialized 2-core fiber, building on 40 years of submarine fiber expertise. Orange handles the French landing and European network integration. This partnership combines Meta's infrastructure vision with specialized manufacturing capabilities.
5Capacity context
1 Pbps could theoretically support 6.25 billion simultaneous music streams. Petal's capacity is 5.5x Meta's first transatlantic cable (Marea) and double their recent 0.5 Pbps Anjana system. The project continues Meta's subsea investment strategy that began with 8 fiber pairs in 2017, progressing to 16 (Amitié) and now 24 with Petal.
6Technical milestones
Petal follows decades of subsea innovation: 1980s EDFA amplifiers, 2010s coherent optical transmission, and spatial multiplexing to overcome Shannon Limit constraints. Multi-core fiber transitions from experimental to mainstream deployment, setting new standards for undersea infrastructure scalability.
7Operational timeline
Scheduled for 2029 service, Petal represents years of collaborative engineering. The project required complete rethinking of cable design approaches, from fiber manufacturing to repeater architecture. Meta aims to establish multi-core fiber as the new baseline for future subsea systems worldwide.
8Strategic importance
As 99% of intercontinental traffic travels via subsea cables, Petal addresses growing bandwidth demands from cloud services and global connectivity. Meta positions this as infrastructure for the digital future, inviting industry-wide adoption of the technologies pioneered in this project.
Original article: Engineering at Meta — Meta's Petal: World's First Petabit Transoceanic Cable