Google and its partner SubCom say the Dunant subsea cable between US and France is now operational; the 4,000-mile cable can carry 250 terabits/second
Context & Ripple Effects
Dunant closes a loop opened in 2018, when Google announced it as its second private intercontinental cable after Curie. The company's subsea program has been compounding since: the 60 Tbps FASTER cable to Japan entered service in 2016 as a multi-party consortium build, while the LA–Hong Kong PLCN project paired Google with Facebook and Pacific Light Cable Network at 120 Tbps.
What changed today is scale and ownership: at 250 Tbps, Dunant carries more than four times FASTER's capacity on a route Google controls outright, and it lands ahead of two more Google-funded systems already in the pipeline — Firmina to Brazil and Argentina, and the 4,350-mile Grace Hopper cable touching Bude and Bilbao.
First-order effects
- Google now owns dedicated US–France transmission at 250 Tbps, removing its dependence on third-party Atlantic capacity for traffic between its American and European data center footprints.
- SubCom banks a completed flagship system for the largest single customer in its market, strengthening its position for the follow-on Google builds (Firmina, Grace Hopper) already underway.
Second-order effects
- Telecom carriers that sell Atlantic transit capacity face a shrinking wholesale customer in Google, which has moved from buying bandwidth in consortia like FASTER and PLCN to commissioning private systems sized to its own demand.
- Facebook and other hyperscalers with European traffic are pressured to match the private-capacity model rather than lease, accelerating their own cable commitments.
Third-order effects
- If the Curie → Dunant → Firmina → Grace Hopper sequence holds, the subsea industry's center of gravity shifts from carrier consortia to hyperscaler-owned infrastructure, with suppliers like SubCom effectively becoming contract manufacturers for cloud companies' networks.
The trend: Transoceanic bandwidth is consolidating into privately owned hyperscaler cable fleets, with Google building one system per major region faster than the consortium model it started with can respond.