The Undersea Lifeline | Motohiro Tsuchiya, Dean of the Faculty of Policy Management
May 26, 2020
I have loved submarine cables ever since I was writing my master's thesis. I can't explain why, even when asked. The cables just lie there on the bottom of the sea, tirelessly delivering optical signals.
In the days before submarine cables had fiber-optic cores like they do today, they contained copper wires. The transmission capacity back then was unimaginably small by today's standards. However, the ability to send a signal to the other side of the planet in just a few minutes in the late nineteenth century, even with manual processing at several relay stations, was nothing short of a communications revolution.
Waikiki Beach in Hawaii would normally be bustling with tourists, were it not for the effects of the novel coronavirus. A short distance from Waikiki Beach, a submarine cable first connected in 1902 still remains on the seabed. If you time it for low tide and swim offshore, you can see the cable clinging to the ocean floor. This is the cable that, about 120 years ago, connected the once-isolated Hawaiian Islands to the world.
Modern submarine cables are buried in the sand on the seabed for several kilometers offshore, as if to hide from the eyes of enthusiasts like me. In the deep sea, however, they are laid directly on the ocean floor. Even at depths of several thousand meters, they do not drift in the water. The cables themselves are quite heavy, and it would be a disaster if they were snagged by a submarine.
Right now, students are staying at home due to the novel coronavirus. Just because they are students at the Shonan Fujisawa Campus (SFC) doesn't mean they are all in the Tokyo metropolitan area. Some students have returned to their home countries and are accessing online classes from different time zones. One of my graduate students is in Turkey. For them, the submarine cable is their lifeline.
Some might say, "What about satellites?" However, geostationary satellites orbiting 36,000 kilometers above the Earth are too slow and have too little transmission capacity. In Japan's case, 99 percent of international communications travel through fiber-optic submarine cables. It is thanks to the terrestrial and submarine fiber-optic networks that we can conduct classes in real time with video.
The other day, there was an online faculty meeting to share the struggles of online teaching. Among the various topics discussed was the issue of students not showing their faces much. Some students may consider the view of their room in the background a matter of privacy, while others may simply want to attend class in a relaxed manner. However, the students' decision to turn off their video cameras is the right one.
The Executive Committee for the Cyber Symposium on Sharing University Remote Learning Initiatives has issued a recommendation titled " A Request for Cooperation in 'Data Dieting': For Instructors Hosting Remote Classes." In it, they state, "It is not necessary to transmit video of the instructor speaking. Constantly streaming video of your face or a document camera during a lecture increases data traffic. Keeping students' cameras on also increases data traffic. Let's turn off unnecessary cameras."
Students probably understand intuitively that keeping their cameras on can make the connection unstable. This is because they are taking more online classes than any single instructor is teaching, and they are learning from experience.
As an instructor, it is somewhat painful to keep talking to a screen that only displays the materials I've created and a list of student names. But when I think about the optical fibers running along utility poles and through underground conduits, and the optical fibers within the submarine cables, all desperately transmitting data, blinking at a dizzying speed, that small pain is nothing at all.
As we strive to prevent the spread of infection, let's also make an effort not to send and receive unnecessary data to ensure smooth online classes and telework. Bandwidth is a limited, shared resource. We will be able to see our students' faces on campus eventually. For now, let's relax, get used to online classes, and enjoy them.