At a glance
- Meta announced Petal on 21 September 2026: a 7,000km cable between the United States and France, rated at one petabit, or 1,000 terabits, a second and due in service in 2029. Meta says that doubles what the largest cables carry over that distance.
- NEC, the Japanese cable builder, will build Petal with fibre from Sumitomo Electric that has two light-carrying cores in each strand, so its 24 fibre pairs do the work of 48.
- Southern Cross NEXT, Australia's largest cable to the United States, is rated at more than 100 terabits a second on four fibre pairs.
- Australian cable company SUBCO announced three 24-pair cables for 2029 the day after Petal, with supply contracts due by early 2027. Meta describes its Waterworth system, which Vocus has referred for a Darwin landing, as 24 pairs too.
- None of the published specifications for the cables due to reach Australia by 2029 mentions two-core fibre.
Meta is building a transatlantic cable that will carry 1,000 terabits a second on 24 fibre pairs, twice what its last cable carries on the same number of pairs. NEC and Sumitomo Electric confirmed their roles in Petal on 22 September, the day after Meta's announcement, and the French telco Orange will bring it ashore in France. Meta has not disclosed the cost or its United States landing point.
An AI factory in Australia that sells computing to customers in the United States or Asia sends that traffic, and the models and data behind it, across the ocean on subsea cables. Deputy Prime Minister and Defence Minister Richard Marles told the Shangri-La Dialogue in 2026 that "around ninety-nine percent of Australia's internet traffic flows through just fifteen subsea cables". The capacity of each cable limits how much of that computing can reach customers overseas.
A fibre pair is two strands of glass, one carrying traffic each way, and the number of pairs has been the industry's shorthand for how big a cable is. Meta's engineers say a single strand of fibre is close to its physical limit, which is why cables have grown by adding strands. Petal's fibre has two cores, two light paths inside each strand, so a cable of the same size and power carries twice the traffic, as Meta sets out in a technical post.
SUBCO announced three new cables for Australia on 22 September, the same day NEC confirmed its role in Petal, connecting Sydney to Japan, Guam to Los Angeles and Perth to Singapore. SUBCO's three cables are due in 2029 with 24 fibre pairs each, like Petal. SUBCO expects to sign supply contracts by early 2027, and the fibre it specifies will decide whether they can carry twice the traffic.
Two light paths in one strand of glass double a cable's capacity
Meta wanted to double its 24-pair Anjana cable across the same ocean and considered three ways to do it: 48 conventional pairs, a wider band of light down the existing 24 pairs as Meta did on the PLCN cable across the Pacific, or fibre with two cores. It chose the third.
Sumitomo Electric's two-core fibre carries two independent light paths inside a strand of the same 125-micron diameter as standard single-core fibre, so Petal's 24 fibre pairs do the work of 48. Meta says the crosstalk between the two cores, the leakage of signal from one path into the other that kept multicore fibre out of long-haul cables, is now close to unmeasurable, helped by running the two signals in opposite directions. Sumitomo has been mass-producing the fibre since September 2023, according to industry publication SubTel Forum.
The cable still needs repeaters, the amplifiers spliced into the cable to boost the fading signal, and Meta says a 7,000km cable typically needs about 100 of them. NEC's new design puts 96 amplifiers in a single housing, with each two-core fibre split into two single-core fibres for amplification and recombined on the other side. The system runs at 18 kilovolts, inside the limit of existing shore power equipment, because Meta says a higher voltage would force the industry to requalify that equipment.
Meta says the design doubles capacity without a matching rise in power or physical cable. Eduardo Mateo, chief strategy officer of NEC's submarine network division, put it on LinkedIn as a cable thinner than a garden hose carrying the equivalent of about 200 million simultaneous HD video streams on roughly the power of two fast electric-vehicle chargers, a comparison he said applies to the undersea equipment alone.
Petal doubles Meta's existing transatlantic cable on the same 24 pairs
Meta's recent transatlantic cables have climbed from eight fibre pairs to 24. Marea, built with Microsoft and Telxius, has eight. Amitié, ready in October 2023, has 16. Anjana, built by NEC and brought ashore in Spain in October 2024, has 24 pairs and carries about 500 terabits a second. NEC calls it the world's first transoceanic 24-pair system. Petal keeps the 24 pairs and doubles the figure.
| Cable (Meta, transatlantic) | Fibre pairs | Design capacity |
|---|---|---|
| Marea, in service 2018 | 8 | Petal is 5.5 times its capacity, per Meta |
| Amitié, in service 2023 | 16 | 400Tbps |
| Anjana, ashore 2024 | 24 | About 500Tbps |
| Petal, service 2029 | 24, two-core | 1,000Tbps |
Source: Meta Engineering, 21 September 2026; NEC, 22 September 2026; DCD, 20 October 2023 and 15 October 2024.
Australia's largest cable to the US has about a tenth of Petal's capacity
Australia's largest international cable to the United States is Southern Cross NEXT, 13,500km from Sydney to Los Angeles with a landing in Auckland, in service since July 2022 on four fibre pairs. Its owners, led by Spark, Singtel and Telstra, rate it on the operator's own pages at more than 22 terabits per pair and more than 100 terabits a second in total. Hawaiki, in service since 2018 between Sydney, New Zealand and Oregon, is rated at 67 terabits a second, according to its equipment supplier Ciena.
SUBCO's SMAP, a domestic cable ready for service in June 2026 between Sydney, Melbourne, Adelaide and Perth, has 16 fibre pairs and is rated at more than 400 terabits a second, more than any international cable in service into Australia. One Petal would carry about ten times Southern Cross NEXT and two and a half times SMAP.
When SUBCO announced its APX East cable from Sydney to Los Angeles in January 2026, Slattery said hyperscalers and AI compute providers planned 3GW of AI factories in Australia by 2028. Carrying their output to the world would need 75 to 150 terabits of international capacity, he said. Firmus took up to 150 terabits on that cable in September 2026. A cable of Petal's capacity would carry Slattery's whole requirement seven to thirteen times over. When APX East reached contract in force on 24 September, he said "the AI factories landing on our shores will demand international connectivity at a scale this country has never had to deliver".
SUBCO and Meta plan 24-pair cables into Australia
Three international cables are due into Australia before the 24-pair systems: Google's Tabua through Fiji to the Sunshine Coast and Sydney by the end of 2026, BW Digital's Hawaiki Nui from Sydney and Darwin to Singapore in 2027, and SUBCO's APX East to Los Angeles in late 2028. Datagrid's Tasman Ring, at least eight pairs from Invercargill to Melbourne, was contracted to the French builder Alcatel Submarine Networks in July 2026.
SUBCO's 24-pair systems, APX North, APX East-2 and APX West, are due in 2029. They add more than 40,000km of cable, and SUBCO expects signed supply contracts by early 2027. Meta's Project Waterworth, a 50,000km system Meta describes as 24 fibre pairs, is the fourth. The environmental referral Vocus lodged for it on 19 June 2026 describes a Darwin landing with branch cables to Townsville and Karumba, and its Australian route survey began in September 2026, according to w.media. No service date has been published.
| Cable into Australia | Fibre pairs | Service target |
|---|---|---|
| Google Tabua (US, Fiji, Sunshine Coast, Sydney) | 16, reported | 2026 |
| BW Digital Hawaiki Nui (Sydney, Darwin, Singapore) | Not published (240Tbps) | 2027 |
| SUBCO APX East (Sydney to Los Angeles) | 16 | Late 2028 |
| SUBCO APX North (Sydney, Guam, Japan) | 24 | 2029 |
| SUBCO APX West (Perth, Jakarta, Batam, Singapore) | 24 | 2029 |
| SUBCO APX East-2 (Guam to Los Angeles) | 24 | 2029 |
| Meta Waterworth (Darwin, Townsville, Karumba) | 24 | Not published |
Source: SUBCO, 19 January, 22 September and 24 September 2026; BW Digital; RCR Wireless, 3 February 2026; w.media, 13 July 2026.
Hamid Maani argued in a guest piece for Certified Strategic in September 2026 that Australia is funding AI factories ahead of the cables that will carry their traffic out, and that each of Australia's three international directions needs at least two more systems. SUBCO's three systems add a cable in each of those directions, and two-core fibre would let each of them carry twice as much on the same pairs.
The new cables terminate in data centres in Australia and New Zealand. NEXTDC supports the Sunshine Coast landing station where Tabua comes ashore from its SC1 data centre and is Google's named landing partner in Darwin and Melbourne.
Equinix hosts the Perth cables and both ends of SMAP, and APX East will come ashore at its SY5 data centre in Sydney, with Digital Realty's Los Angeles landing station at the United States end. CDC is a named New Zealand partner on Google's Honomoana, which comes ashore at Orewa north of Auckland.
Will two-core fibre reach Australia's cables before 2030?
NEC has engineered and qualified a complete system around Sumitomo's two-core fibre for Meta, the fibre has been in mass production for three years, and the first cable to use it is contracted for 2029. Petal is 7,000km. SUBCO's Pacific routes run 9,500km to 13,000km, and no two-core system of that length has been announced.
SUBCO's APX East is the furthest along. It signed its supply contracts in September 2026, manufacturing starts in October and the first section is due to be laid out of Sydney in August 2027. SUBCO's three 2029 cables are due to reach the same stage by early 2027, and Waterworth, which shares Petal's owner, is still surveying its Australian route.
We expect Meta's Waterworth to be the first cable into Australia specified with two-core fibre, because Meta has qualified the system with NEC on Petal and its Australian segment has not reached the point where the fibre is fixed. For SUBCO's three systems the choice rests with whichever supplier wins the contracts SUBCO expects to sign by early 2027. A 24-pair cable with two cores sells 48 pairs' worth of capacity inside the cable and power envelope of 24, the trade-off Meta's engineers set out when they chose it.
Every AI factory in Australia that sells computing overseas depends on international cable capacity for the life of the cable carrying it. Firmus's agreement for capacity on APX East runs 25 years, and APX East will take almost three years from announcement to service. A cable built in 2029 with single-core fibre will carry half what the same cable could carry with two cores, for as long as it is in the water, on Pacific routes up to twice Petal's length where each replacement takes years to plan and lay. AI factories are going up wherever power and land allow, in Australia and overseas, and the cables between them carry what those factories sell. Two-core fibre doubles that capacity on a cable of the same size.
What to watch
- SUBCO's supplier. SUBCO expects signed supply contracts on APX North, APX West and APX East-2 by early 2027. The supplier SUBCO names, and whether its specification says 24 fibre pairs or 48 core pairs, will show whether two-core fibre reaches Australia by 2029.
- Two-core fibre at Pacific distances. Petal is 7,000km. An offer of two-core fibre from NEC or another builder on a route longer than 10,000km would open it to the trans-Pacific cables into Australia.
- Waterworth's Australian specification. Vocus's environmental referral describes the route; Meta has not published the Australian segment's capacity or fibre design. The route survey that began in September 2026 is scheduled to run about six months.
- Petal's United States landing and cost. Meta has disclosed neither.
- Tabua switching on. Google's cable into the Sunshine Coast and Sydney is due in service by the end of 2026, ahead of every 24-pair system.