The first mainframes in universities and government research labs communicated with each other using the phone line. When the personal computer took off, home users would also rely on their phone connections. Gradually, that changed, and while DSL connections used to be standard, most home internet users in cities connect using coaxial cables today.
However, that’s starting to change now that companies and city governments are starting to install fiber cables. Fiber-optic cables use special strands of glass: when you flash a light at one end, it’ll come out the other side at nearly the speed of light. That’s much faster than moving electrons, which is how electricity moves both energy and information. In fact, depending on the cable connection a fiber internet line could be 10-100 times faster, and fiber connections don’t have to share that speed between neighbors the way cable does.
But what about where we are today? Is this the best speed we can hope to reach? Researchers at the University College London disagree. In a recent experiment, they managed to transmit 15 light pulses through the same glass tube simultaneously, and they calculated they could send over 1 terabit per second instead of 1 gigabit.
The reason this works is simpler than it seems. When you see something white, what you’re really seeing is several color wavelengths all at once. Your eyes combine them and call it white, but if you let light move through a prism the colors will separate and you can measure them individually. What the researchers did was carefully send several wavelengths with a different pattern for each one, and then the receiving end separated the light waves to get different information from each one.
Unfortunately, this new idea won’t be showing up on the fiber internet cables that cities have today. The technology still needs a lot of work to perfect, and so far the researchers have needed special fiber cables, so using the new technique demands more than just a quick fix. Terabit internet might be in our future, but it’s not here just yet.
Still, it’s good to know that today’s high speeds will someday become even faster. Fiber internet is the way of the future, at least for landline internet, and a new kind of fiber-optic cable will eventually replace the ones we have today. It happened to phone lines, it happened to cable connections, and there’s no sign that speed improvements will ever slow down.