I have been an AT&T U-Verse Wire Technician for over 7 years.
What Is fiber?
Fiber is, quite literally, a long strand of glass that's about as thick as a strand of hair on your head yet is capable of tremendous speeds! Making fiber optic wiring is interesting and is a process much too long to write about.
History of Fiber
Fiber is relatively new to the consumer but the technology behind it has been around since Alexander Graham Bell and the 1880s. No, that's not a typo, the 1880s.
After Bell invented the telephone, he invented another device called the Photophone. The photophone used light as a source of transferring data, specifically sound. A very thinly curved mirror had a light shining into it to be reflected to the receiver at the other end. The sender would speak into the back of the mirror. The vibrations (or frequencies) in their voice caused the mirror to distort the reflection of the light. The reflections of the light were then received (at light speed) at the other end.
This isn't quite fiber optics, but it's the same concept. Fiber uses light signals, or pulses, that are received and decoded into usable data such as visiting Hubpages and watching the video below to see a Photophone in action.
Let There Be Light!
Now we know that fiber is a hairlike piece of glass that light can shine through. Is it magic light? Not really, but kind of yes. Take a second to look around right now. Seriously, look around you. You see all the colors? What if I told you there were dozens of colors all around you that you couldn't see? Would you believe me? It's true. Color is simply light or the reflection of light. Let's take a brown crayon for example. That crayon is actually not brown. It's white, green, red, blue, violet, etc... That crayon is every color except brown. So why does it look brown? That is because the only light that it reflects is a brown light, so we see brown. To be more accurate, the only light visible to us that it reflects is brown.
The colors we can't see are often called ultraviolet. Let's try something. Do you have a TV remote near you? Aim it at your face and press a button. Did you see any colors? Unless you're an alien, you didn't. Now, aim that remote at the camera on your phone and press a button. See the color now? That's a color we can't see. So when you aim your remote at your TV and press a button, you're simply shining a flashlight at your TV and only your TV can see that color.
More About Fiber
So we have this one tiny piece of fiberglass that we can shine a light through so a receiver can decode it into a usable signal. At the speed of light, that little piece of glass hair can send you 1 gigabyte (GB) per second. That is insane if you really think about it. In theory, you could download an entire movie in high definition in about 4 seconds.
But wait, there's more! That one hairlike fiber can be used for multiple streams of data! Let's use the names of light we know. Let's say we shine a red light through that fiber. That light is actually pulsing. Data is transmitted in 1s and 0s. So red light on = 1, red light off = 0. What if the receiver only sees red light? Then, we can use a second receiver that only sees blue light. So now that fiber optic cable has flashing red and blue lights flying down the road faster than a police car headed to a donut shop. The red receiver sees and decodes the red lights while the blue receiver decodes the blue lights. The lights don't interfere with one another since light travels in wavelengths. Those wavelengths may cross paths but don't distort the original color.
We can do this at AT&T with up to 64 different lights on a device called a splitter. That splitter doesn't decode, but it acts as a filter. Now there's one little fiber optic sending all these colors. A splitter will actually let red light pass to a new fiber optic cable. Then it will let all the blue light pass to a 2nd fiber optic cable. Then, the green light is allowed to pass to a 3rd, and so on. From 1-64, these are ultraviolet lights that are now separated into individual streams that go to your house or your neighbor's house with practically zero interference or sharing of bandwidth.
One single fiber optic line can be split into 64 separate lines (most are only split into 32) for home use in a box called a PFP. My job is to look at my invoice and see if you're on splitter 1 (there are multiple splitters) and access port 16. So if I go to splitter 1 and find the 16th fiber (called a port), I'll find your service.
How Fiber Goes From the Street to Your House
You now have service at the PFP which is at the front of your neighborhood. How does it get to your house? Well, there's a second set of wires in that PFP that go directly to a terminal, either at the top of a pole or to an underground enclosure, near your house. All I have to do is look at my trusty invoice that is never wrong (sarcasm). You are on the #168 OUT fiber. I can use a laser light to verify. I put a laser on the fiber at your terminal and go back to my PFP to make sure it's where it's supposed to be. I simply plug your splitter 1, port 16 into, OUT port 168. Now that light is shining all the way to the terminal near your house.
From there, I run a drop. These are the lines that hang from the telephone pole to the house. Some of them can be buried underground as well. That fiber drop goes all the way into your house. No splices. Then we mount a smaller fiber receiver onto your wall called an ONT. That ONT is what's going to decode those blinking lights into a usable signal. It then puts that signal onto an ethernet wire that plugs into your modem. Just like that, you have fiber optics!
I've taken some pictures of the process and posted them below. It's a relatively simple process really.
Fiber Optics Pros
- Fiber is very fast.
- Fiber has near unlimited bandwidth.
- Fiber does not suffer from some issues that copper can have such as shorts, grounds, voltage, etc... You can literally lay it in water for months and it'd be fine.
- Fiber is literally light speed so I can't see how it can get faster.
- Fiber does not suffer from attenuation. Which means, it can be miles long with no loss of signal strength.
Fiber Optics Cons
- Extremely fragile.
- Not many devices can utilize the speed it offers.
- There's very few things that can be done to repair fiber optic cable other than replace the entire thing.
Fiber Speed Expectancy
I can't write about fiber gigapower without talking about this, because it is really important for fiber users to understand. We get a lot of people who sign up for fiber gigapower and then call in a repair every two days because they're not getting 1 GB per second. Your device (XBOX, Playstation, Cell Phone, Laptop, etc...) is limited to a certain speed. It's the hardware, the physical network adapter built into it, that limits the speed. Also, getting those speeds on Wi-Fi is extremely difficult if not near impossible. We cannot fix this issue.
We also can not fix buffering with Netflix or Youtube. You can download a video at 1 GB per second, but no one is sending you information that fast.
If Netflix uploads a video to you at 12mbps, then that's as fast as you're going to get it. If your Red Dead Redemption video game is sending you information at 24mbps, that's as fast as you're going to get it.
Fiber has capabilities that the rest of the world is not yet using.
What Do All These Acronyms Mean?
- At&t Language, Accronyms, and Telephony Talk
Telecommunication acronyms and terminology for AT&T. Learn how to speak the telephone language... or at least what some of the words are. Look, there are pictures, just look at the pictures.
I'm not a fiber expert and there's a lot of details I've left out or glossed over as to not confuse. If you have any questions, please don't hesitate to ask! I hope you enjoyed the quick fiber run down!
This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.
© 2018 Clyde King
Diocia on June 21, 2020:
"This is the ONT that decodes all those pretty blinking lights. Once the signal is decoded, it leaves on the yellow ethernet going to the modem."
Technically the ONT is the modem, and the black box you plug it into is just the router.