In our digital age, submarine data cables are critical infrastructure. Modern society is becoming more dependent on the smooth working of subsea cables.

Earlier this year the Australian Bureau of Meteorology even proposed a subsea data cable to Antarctica. Icebergs could be a problem in damaging the cables. But there’s no doubt such a connection would bring improved connectivity to our polar stations and raise our Antarctic leadership profile.

Our dependency on the submarine cable network will increase substantially with the growing use of the internet, the importance of cloud storage and future services provided by 5G networks and the Internet of Things.

In the Indo-Pacific, submarine cables carry more than 95 per cent of international data including phone and data communications traffic. Our Zoom meetings, emails, hotel reservations, and financial transactions depend on it.

But these cables are vulnerable to a variety of risks and threats. Small island nations are particularly exposed due to a lack of redundancy. Tonga, for example, was disconnected in 2019, hampering airline and hotel bookings, money transfers, phone calls and social media access for several weeks.

Submarine cables are laid, owned and maintained by the private sector. But governments have a responsibility to ensure the infrastructure conforms to security standards and that there’s sufficient redundancy to ensure resilience.

The geopolitical importance of the submarine cable network is growing: carrying data is critical in the information age. As China emerges as major Indo-Pacific cable player, risks of espionage and industrial sabotage have grown.

Fishing and anchoring contribute to much of the damage to submarine cables. Earthquakes, volcanic eruptions, tsunamis and landslides feature among non-human threats. Sabotage, interference, tapping and terrorism are persistent threats. The level of technical expertise and resources required to damage submarine cables isn’t high.

Submarine cable locations, including landing sites, are publicly known, allowing interference by adversaries. The difficulties of interfering with cables deep underwater mean landing stations represent a key vulnerability to data transmission security. In the event of submarine cable damage, disruption, faults or breakage, prompt access for repair crews is critical, especially for Pacific island countries. But repair vessels are often delayed by long travel times to distant fault locations and coastal state approvals.

A regulatory gap exists in submarine cable protection: many Indo-Pacific states don’t criminalise conduct that has the potential to damage or interfere with cables. International legal protections are inadequate to regulate the complex ownership structure of cable infrastructure, which don’t fall under the jurisdiction of any one country when laid in the high seas. Additional legal issues arise when submarine cables traverse disputed maritime boundaries.

China is an emerging submarine cable supplier. It’s part of the Chinese ‘Digital Silk Road’ strategy. HMN Technologies, (formerly Huawei Marine Networks) is majority owned by Shanghai-based Hengtong Optic-Electric. It has a global market share of about 10 per cent and built or repaired almost 100 of the world’s 400 submarine cables. This year, the World Bank-sponsored East Micronesia Cable tender was cancelled due to fears HMN would win. It would have connected Nauru, Kiribati and the Federated States of Micronesia. Nauru is now talking to Australia about connecting the island nation to the Coral Sea Cable, which is partly owned by the Australian government.

Australia should join with like-minded democracies in the Quad, and others such as Britain and France to share risk assessments on cable projects and discuss how they can work better together to protect submarine cables. These nations should be developing contingency planning with industry on possible attacks on cable networks or major breaks and monitoring China’s cable proposals with regional states.

They should pool financial support to smaller countries in the Indo-Pacific that forego cut-price Chinese cable options. Three years ago, Australia largely paid for an undersea internet cable system for Papua New Guinea and Solomon Islands, shutting out rival plans from Huawei. We’re partnering with Japan and the US to finance an undersea cable for Palau.

Like-minded democracies should be sharing information on matters relating to sabotage and espionage of submarine cables and support their own companies that own and operate cables. Their joint military exercises, including desktop exercises, should include submarine cable contingencies, especially scenarios where many cables are severed in a short time period.

Democratic like-minded states should monitor Chinese oceanographic research and survey vessels that might engage in submarine cable sabotage or espionage. They should support information sharing by Indo-Pacific states on suspected cable attacks and co-operation by regional states in the event of an attack or other disruption to cables.

Secure submarine cable connections should be part of capacity-building projects with our Pacific neighbours.

Like-minded democracies should produce guidelines on best practices in cable governance regimes, such as establishing cable protection zones to prohibit or restrict activities where damage might occur. It’s time to start the conversation on an international treaty for the protection of submarine cables.