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Diving Into Subsea Fiber Optic Cable Networks


When was the last time you called a friend overseas or sent a file to a coworker on another continent? You probably didn’t think about how your message was transmitted. We rely on a vast network of submarine fiber optic cables to exchange data and communications overseas every day.

In this blog, we’ll dive into why subsea networks are important and where Zayo comes in.

What are subsea fiber optic cable networks?

A subsea network is a system of undersea optical fiber cable laid on the sea and ocean floor that connect continents and countries via telecommunications signals. They run from a couple of dozen miles to over 24,000 miles long and last for an average of 25 years.

Today, there are more than 400 submarine fiber optic cables transmitting intercontinental data and messages worldwide. And they get the message across quickly: subsea fiber optic cables can transmit data in terabits per second.

These extensive and important submarine cable networks are traditionally owned and operated by telecommunications companies. Increasingly, Internet companies and hyperscalers own and operate these cables, as well.

Why are subsea networks important?

Subsea networks answer important global connectivity needs. Two major global market trends are driving the need for subsea networks: the demand for increased capacity and globalization.

First, the pandemic led to a surge in Internet traffic and a demand for greater capacity. Submarine cable networks have helped to provide the capacity needed to accelerate digital transformation. As more next-generation applications hit the market, greater subsea cable capacity is needed across the board. In fact, network capacities are increasing by 25-50% every year.

Next, globalization is urging the expansion of subsea networks. The communications and data transfers that we depend on to keep us globally connected require the infrastructure to support them. In fact, over 95% of international data and voice transfers are carried over subsea cables.

The overall economic value of undersea cables is tough to precisely measure. However, experts estimate that subsea networks contributed $649 billion or 3% to the US GDP in 2019.

Zayo’s undersea connectivity

Zayo remains at the forefront of global connectivity with our submarine network offerings. We offer capacity on over 30 strategically placed undersea cables worldwide chosen for diversity and low latency. Our fully diverse subsea network connectivity and PoP design allows for high-availability, low-latency connectivity. This vast network of undersea cables connects sophisticated and growing economies around the globe.

Our fully owned and operated subsea cable ZEUS connects key markets in the UK and Netherlands. ZEUS is double-armored and was built to the latest sustainability standards and offers up to 400G of reliable bandwidth.

Our customers are global organizations – hyperscalers, financial powerhouses, and multinational organizations – that require global connectivity. These innovative companies require redundant, reliable networks to connect with their customers, employees, and partners worldwide.

Zayo provides global, subsea connectivity in every continent except Antarctica – but we aren’t finished growing our global network yet. Our latest investments include augmenting our high bandwidth, reliable connectivity overseas in Tokyo, Johannesburg, and Sao Paulo.

Our efforts to connect our customers and the world don’t stop with subsea networks. We’re expanding our footprint and adding capacity and redundancy to our existing terrestrial fiber cable routes, too. The end goal is to increase performance and cut costs for our customers and support the next generation of innovations worldwide.