Subsea cables: invisible but critical infrastructure
Underwater networks are the lifeblood of global and economic connectivity, carrying over 99 percent of the world's intercontinental electronic communications traffic. But the challenge is to keep data flowing reliably while maximizing optical spectrum efficiency.
This complex and integrated system is becoming even more critical as AI-originated traffic from far-off locations demands more power, better connectivity, and increased space for data centers. And as a result, submarine cables are now required to land in previously unconventional locations – away from populated areas and closer to power sources.
400G: the new 100G
Within this context, 400G is fast becoming the new 100G. The increased capacity is the new baseline that submarine cables need to operate at to be successful at transmitting AI-generated data back and forth between remote data centers and terrestrial networks.
To prepare for this extra bandwidth, the industry must ensure scalable networks are in place that will be able to respond to AI-induced demand, fast. This involves not only deploying the latest fiber technology but also making significant investments in new infrastructure to meet these challenges.
$300-400m
cost per cable
The need for new pathways
Some of the key challenges of subsea connectivity include issues caused by cut cables, outages, and bottlenecks in traffic due to increased bandwidth demand. For these reasons, the diversification of network cables and alternate paths for traffic are crucial – particularly for transatlantic connectivity.
However, laying new cables is a time-consuming and expensive process, taking years from planning to completion and costing around $300-400 million per cable1. To expedite these projects and navigate political and regulatory hurdles quickly, private investment is often required.
So, what’s the answer?
25-70%
of data traffic flowing between Asia and Europe was affected
The challenge of cut cables
Cut cables have become a real challenge for subsea cabling providers in recent years. Whether through accidental circumstances, for instance damage caused by shipping activity; or through malicious intent, such as politically or financially motivated activity, cut cables can disrupt the operations of hyperscalers and enterprises – with severe knock-on effects for end users.
Recently, a total of 4 of the 15 undersea communications cables in the Red Sea were severed, affecting an estimated 25-70% of data traffic flowing between Asia and Europe2/3. Meanwhile, cable cuts on the Eastern Africa Submarine Cable System (EASSy) caused disruption to internet services across the whole of East Africa4.
25%
of data traffic flowing between Asia and Europe was affected
The challenge of cut cables
Cut cables have become a real challenge for subsea cabling providers in recent years. Whether through accidental circumstances, for instance damage caused by shipping activity; or through malicious intent, such as politically or financially motivated activity, cut cables can disrupt the operations of hyperscalers and enterprises – with severe knock-on effects for end users.
Recently, a total of 4 of the 15 undersea communications cables in the Red Sea were severed, affecting 25% of data traffic flowing between Asia and Europe2. Meanwhile, cable cuts on the Eastern Africa Submarine Cable System (EASSy) caused disruption to internet services across the whole of East Africa3.
1 https://www.retailbankerinternational.com/thought_ leaders/ subsea-cable-outages-impact-investment initiative
2 https://www.bbc.co.uk/news/world-middle-east-68478828
3 https://developingtelecoms.com/telecom-technology/optical-fixed-networks/16697-east-africa-internet-disrupted-again-by-new-subsea-cable-cuts.html
1 Retail Banker International, EXA Infrastructure, The 3 I’s of the subsea cable outages – impact, investment, and initiative, 2024
2 HGC Global Communications, Statement - Supplementary information of HGC Global Communications regarding submarine cable damage in the Red Sea to demonstrate Hong Kong as international telecommunication hub, March 2024
3 RETN, Building the networks together, Oct 2024
4 Citizen Digital, What to know about submarine cable cuts behind East Africa internet outage, May 2024
