Australian network builder SUBCO has announced plans to build an 850km terrestrial fibre network connecting Sydney and Melbourne, adding a new high-capacity inter-capital route to its growing subsea infrastructure portfolio. The SM-1 network will have a minimum of 96 fibre pairs and is intended to provide direct connectivity between the two cities, which host the majority of Australia’s data centre and cloud infrastructure.
SUBCO said the route is being developed in response to increasing demand for low-latency, high-bandwidth connectivity between the Sydney and Melbourne markets, driven by hyperscale cloud infrastructure, AI workloads and enterprise data requirements.
The company said SM-1 will connect cable landing stations, carrier-neutral data centres and cloud on-ramps in both cities, providing an additional route between the markets and reducing reliance on existing inter-capital fibre networks. Survey notices have been issued and SUBCO expects to have the required permits in place, with construction commencing immediately. The company is targeting a Ready for Service date of June 2028.
Bevan Slattery, founder and co-CEO of SUBCO, said Sydney and Melbourne account for the “overwhelming majority” of Australia’s data centre capacity and cloud infrastructure, with demand for diverse connectivity expected to increase as AI and hyperscale workloads expand. “SM-1 gives our customers a purpose-built, high-capacity terrestrial path that complements our subsea network and ensures they have the infrastructure to scale without constraint,” he said.
The project adds a terrestrial component to SUBCO’s broader network expansion, which includes the 5,000km SMAP submarine cable linking Sydney, Melbourne, Adelaide and Perth. SMAP entered service in June with 16 fibre pairs and more than 400Tbps of capacity.
SUBCO is also developing the APX programme, a series of three subsea cable systems connecting Australia with Asia and the US. APX North is planned to run 9,500km from Sydney to Japan via Guam, while APX East-2 will span 10,000km between Guam and Los Angeles. APX West will cover 4,600km between Perth and Singapore, with branches to Jakarta and Batam. Each system is planned to have 24 fibre pairs, with SUBCO targeting completion of the three systems by 2029.
The APX systems are designed to add international route diversity and capacity as demand for connectivity between Australian data centre markets and overseas cloud and AI infrastructure grows.
Together with SMAP and SM-1, the projects will give SUBCO a network spanning international subsea routes and domestic inter-capital connectivity, linking Australian data centre markets with major connectivity hubs across the Indo-Pacific.