The Internet and Fiber Optics
Key: AWL to Study, Low-frequency Vocabulary
What is the connection between the Internet
and fiber optics?
The Internet
• The Internet has been lauded as the greatest
innovation of the 20th century.
 conceived by the US Federal Department of Defense
 grown into a global network
 revolutionized global communications, information access,
and commercial transactions
For what purposes do you use the Internet?
A Complex System
• Visual representation of the Internet resembles the
human brain.
• Allows for instantaneous communication
• Provides instant information
 search engines and websites
• Broadens social circles
 online forums and message boards
How is the Internet like the human brain?
Increasing Internet Speed
• Fiber Optics is a data-delivery system.
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transmits light through glass fibers
connects the developed world
deployed in intercity and transoceanic communication
delivers clear and secure signal
delivers information 1000 times faster and 100 times farther
than copper-wire technology
Why do you think fiber optics is not used
extensively within cities?
How Fiber Optics Works
• Light source adjacent to the fiber
laser produces and digitally encodes signal
light travels through core of glass
mirrored layer reflects light off walls
light moves through channel
Using the diagram, explain how fiber optics works.
Signal Loss
• To make up for signal loss over distance
 laser amplifiers convert weakening signal into a stronger one.
 Upon reaching its destination, an optical receiver decodes
the digital signal, so it can be read by a computer, TV, or
telephone.
Physical Constraints
• Creating a fiber optic infrastructure in cities is difficult.
 need to distribute fibers to millions of users within one city
• Fiber optics has been reserved until recently for
long-distance applications.
What is meant by the phrase “fiber optic infrastructure”?
Telecommunications
• Telecommunications companies solve “last-mile”
connectivity problems by complementing fiber with
existing copper-wire systems.
To what does the phrase “‘last-mile’ connectivity
problem” refer?
Fiber-to-the-neighborhood
• FTTN delivers fiber optic service to an area where
cable or DSL copper-wire provides high-speed
Internet.
• Cable and DSL are intermediate measures.
 Bandwidth is inferior to fiber.
 They provide adequate service without huge undertaking of
replacing and rerouting fiber to individual residences.
Fiber Optics for the Future
• Internet traffic is estimated to increase fifty-fold
within next two years.
• Light colors that can be routed through a fiber
doubles every six to nine months.
 Bandwidth potential of fiber is limitless.
 3-D virtual world applications will
demand faster connection speeds.
What kinds of 3-D computer applications do you know?
Fiber-to-the-home
• Asian countries have taken the lead with FTTH
technology.
• The not-so-distant future:
 FTTH will be the standard international medium of Internet
connectivity.
Why do you think Asian countries have taken the lead
with FTTH?