How does a method of communication, say an e-mail or phone call make its way into an underground/underwater fiber optic cable?



How does a method of communication, say an e-mail or phone call make its way into an underground/underwater fiber optic cable?

In: Technology

Origin and destination. If you are in the US and send a chat to China it will transit a submarine fiber optic cable. It’s very common. FYI so are submarine copper cables for areas that lack density for fiber and the associated equipment.

Your phone digitally encodes your analog voice waves into 1s and 0s through a process called sampling. These digital 1s and 0s are nothing more than voltages switching on and off, or between a higher and lower voltage (5 volts for a “1” and 0 volts for a “0”, for example). The phone sends a radio wave modulated by these 1s and 0s to the cell tower. The cell tower receives this signal along with others, and multiplexes or shuffles the multiple data streams from other phone calls together, and sends the data over a fiber optic cable connected to a backhaul network, which connects to the core network consisting of fiber optics, switches, routers, and frames. The data stream travels to its destination using address bits and other overhead data for routing, and the recipient’s phone decodes the voice data received from its own local cell tower and converts it back into an analog waveform which is sent to the phone’s speaker. The process is similar for landlines, except there the analog audio is routed to a local switching office (central office) which does all the digital encoding and multiplexing with in-house equipment.

The computer converts the data to a series of zeroes and ones, which then get converted into electricity on and off/light on and off, then reconverted at the other end.

Not quite the right analogy but think of it as a bit like a fancy SOS signal sent in morse code with a torch, that someone can write down at the other end because they know what the dots (short flashes of torchlight) and dashes (long flashes of torchlight) mean.

Your computer takes the email letters/words and sends pulses of electricity through cables (your network cable, router, modem, cable/phone cables on the street). Those cables lead to the underground and underwater cables. Everything is connected by cables. Just like you can drive anywhere in your car if there are roads connecting you to the place.

Every letter or word has a special pattern of electric pulses, which a computer can understand. Like 0010100 (off, off, on, off, on, off, off) might be a certain letter, and a different pattern is a different letter. So you can send communication through cables using electricity…as long as your computer knows how to encode it, and the receiving computer on the other end knows how to decode it.

I’m leaving out some steps, but that’s pretty much it.