Fiber and Bandwidth - Q & A

Q: What is bandwidth?
A: In a network, bandwidth is the ability to carry information. The more bandwidth you have, the more information can be carried in a given amount of time.

Q: How much bandwidth - or information - do we need?
A: A standard-definition television signal requires a bandwidth of about 2 Mbps - two million bits (zeros and ones) per second. HDTV requires as little as 4 Mbps if the image is rather static - a person being interviewed, for instance. But fast action, such as some sporting events, requires more - as much as 8 Mbps, even with new compression technology such as MPEG4.

Q: What about data?
A: Bandwidth requirements are exploding for many kinds of data. Most new digital cameras create images that contain 2 to 15 megabytes.

Q: What are some of the advantages of fiber?
A: Optical fiber is unique, in that it can carry a high-bandwidth signal enormous distances. Fiber uses laser light to carry the signal. Under most circumstances, the signal can travel 12 miles (more than 20 kilometers) without degrading enough to keep it from being received.

What's more, the equipment necessary to send the light signals keeps getting better. So equipping an existing fiber network with newer electronics and with lasers that pulse light faster, or lasers using different wavelengths of light, can vastly increase the available bandwidth without changing the fiber itself. That's why fiber networks are said to be "future proof".

Q: That sounds like magic. But isn't fiber too new to trust?
A: Fiber has actually been used in communications networks for more than 30 years. But until 2002, it was rarely used to deliver a signal directly to a home. Instead, it was - and is - relied upon to carry communications traffic from city to city or country to country. Almost every country on Earth has some fiber, delivering services reliably and inexpensively. In fact, if you have a cable modem, with broadband supplied by your cable operator, or if you have DSL, which converts your phone line into a data pipeline, you are already using fiber. The fiber carries the signal close enough to your home so that copper can carry it the rest of the way.

Q: Isn't that good enough?
A: That depends on what you want to use your bandwidth for. If all you want is to send simple text emails or receive an occasional photo of your grandchildren, the bandwidth provided by today's cable modems and DSL lines is good enough. But as soon as that photo becomes a video, you'll need more.