As the science fiction of tomorrow's internet becomes science fact, Bloomington's own approach to citywide broadband might appear archaic to the casual observer — but only at first.
The city's current venture into high-speed internet transmitted by buried cables looks dated in a world with wireless, but a basic understanding of what the information delivery system is, how it works and the benefits generated by a 100-percent fiber network versus alternative methods may give insight as to why it's a priority. Although universal wireless internet and information sent by lasers over thin air may sound appealing, experts say a fiber infrastructure is the immediate future of fast internet.
"You can send more information over a strand of fiber than you can an equivalent strand of copper or than you can send through the air — and it’s a lot more information," said Steven Wallace, enterprise network architect for Indiana University. "It’s hard to conceptualize how much more information. It’s not infinite, but it is darn close."
So how does it work?
It's a mistake to equate the fiber used in an internet infrastructure with the fiber optics used in novelty lamps, even though both strands use a similar phenomenon called total internal reflection to transmit light.
Wallace said fiber was introduced as a material for mainstream communication in the 1970s. Several components are within each fiber-optic cable. At the center lies a filament of glass one-tenth the width of a human hair that directs the actual transmission of information. That glass core is contained within a slightly larger tube made of a different glass material. That different glass — and the nearly nonexistent space between those glass strands — helps light travel through the core.
"Because the center piece is so small, the light doesn’t really bounce around, it just follows it smoothly," Wallace said. "It acts like a wave guide. You have very little light loss per unit of distance, and the signal integrity over that distance is much greater than over copper or the type of stuff you see in those lamps at the novelty store."
All of that is contained within several layers designed to protect the fiber cable. A cable may contain several of these strands of fiber, allowing for a greater use of the space within an underground pipeline, known as a conduit.