If you’re anything like me, your internet connection is a connection to family, to friends, to work, to business partners, to entertainment – and everything in between. When people think of the internet these days, “the cloud” often comes to mind, for storage and apps and streaming games and videos, regardless of your location or your device.

But most people don’t really give much thought about what’s behind the scenes, what’s powering the internet and the cloud. Would it astonish you to know that subsea cables are the invisible force driving today’s internet? That’s right. When you’re binge watching your favorite show, or watching your two hundredth funny cat/dog/goat/horse video, or saving the world in an alternate online universe, infinite amounts of that data are traveling across the bottom of the ocean. While satellites might seem the more likely approach for data delivery, physical cables laid across ocean floors are capable of far more capacity and lower latency.

Subsea cables aren’t a new concept. The first transatlantic cable was completed in 1858, connecting the United States and Britain via telegraph. Queen Victoria sent a congratulatory message to President James Buchanan – the message took around 17 hours to deliver, at a rate of 2 minutes and 5 seconds per letter by Morse code. Not exactly up to internet era standards where everyone wants more, faster.

subsea cables cisco

Today’s subsea market is booming, with around 378 submarine cables in service around the world, spanning over 1.2 million kilometers (according to TeleGeography), delivering petabytes of information around the globe daily. Hyperscale players like Google, Facebook, Amazon and Microsoft own or lease more than half of the undersea bandwidth.

So how does it work? Subsea cables use fiber optic technology. At its basic level, fiber optic communication is a method of transmitting information from one place to another using pulses of light sent through an optical fiber. Lasers on one end fire at extremely rapid rates down thin glass fibers to receivers at the other end of the cable. A subsea cable itself is usually roughly the size of a garden hose, made up in a large part by protective and insulation layers due to the harsh undersea conditions in which the cables must function. The actual filaments that carry the light signals are extremely thin, about the diameter of a human hair. Fiber optic cables carry these laser signals at a rate of terabits per second.

Where does Cisco fit into this subsea cable world? Cisco continues to be a leading optical transport vendor driving this evolution. Our optical networking solutions enable us to tailor the light signals for the best performance for such a long distance, without wasting any precious spectrum. We put multiple channels onto a single fiber by giving each channel its own color of light, or wavelength. And, we put as much capacity as possible onto each wavelength and then combine many wavelengths onto a single fiber.

In the past few months, we’ve had unprecedented momentum in both the subsea and terrestrial markets – made noticeable with several recent announcements, including deployments with Superloop and AARNet, as well as a MAREA subsea cable trial. In this trial, we demonstrated 26.4Tbps over 6,600 kms of subsea cable, from Virginia Beach in the U.S. to Bilbao, Spain. This 26.4Tbps performance surpasses all other deployments to date, setting a global spectral efficiency record. Think of spectral efficiency as a measure of how efficiently we used the fiber’s total available capacity.  In layman’s terms, we delivered the maximum amount of data that can be transmitted in the available spectrum.

When the internet emerged in the mid 1990s, we were astounded by its disruptive influence. It was merely the beginning. By 2022, more IP traffic will cross global networks than in all prior “internet years” combined up to the end of 2016 (according to the Cisco VNI). In other words, more traffic will be created in 2022 than in the 30+ years since the internet started. That’s less than three years away! As the world continues to demand videos, apps and gaming – and as we look to the future of self-driving cars, artificial intelligence, and virtual and augmented reality – the internet and its rapid, reliable connectivity will only continue to grow as a powerful force that shapes our world and future.

Learn how the Cisco NCS 1004 is helping our customers keep up with current and future demands with more capacity, longer distance and lower cost per bit.


Bill Gartner

Senior Vice President/GM

Optical Systems & Optics Group