Meta Announces Petal, First Petabit-Class Transoceanic Subsea Cable

Meta's Petal cable represents a major infrastructure bet on the bandwidth demands of the AI era. The system will be the first transoceanic cable to deliver petabit-class capacity — doubling the throughput of today's most advanced subsea cables — connecting France and the United States over roughly 7,000 kilometers. Meta says it will be the first system to deploy multi-core fiber technology at scale, a step-change in how much data a single cable can carry.

The technical leap is multi-core fiber: rather than a single light-carrying core per strand, multi-core fiber packs several cores into one fiber, multiplying capacity without proportionally increasing cable size. Deploying it at transoceanic scale is a significant engineering milestone, and Meta's engineering blog details the connectivity and physical-layer challenges involved. Service is expected in 2029, reflecting the multi-year timelines inherent to subsea infrastructure.

The strategic logic ties directly to AI. Training and serving frontier models, plus Meta's push into always-on AI agents like Muse and generative features across Instagram, Facebook, and WhatsApp, generate enormous transatlantic data flows. Owning petabit-class capacity gives Meta control over a critical cost and reliability variable rather than leasing from third parties. The announcement also lands the same week a Reuters report noted the US halted East Coast flights after a fiber-line cut — a reminder of infrastructure fragility that drew commentary on Hacker News and underscores why hyperscalers are increasingly building their own resilient, high-capacity backbones rather than depending on shared cables.