This week, a repair team is set to help restore Tonga’s internet, after a volcanic eruption and tsunami last month severed the country’s primary communication connection to the rest of the world: a submarine cable, one of many that crisscross the floors of oceans and seas around the planet. In fact, if you’re listening to this outside of the U.S., this episode has itself traveled along a cable, or multiple cables, at the bottom of the ocean to make its way to you. To unpack this technology, we’re joined by Alan Mauldin, a research director for market research and consulting firm TeleGeography.