Fiber optic speeds

Crystal Ball Gazing Reflections on the role of information resources in a liberal arts eduction
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The speed of today's fiber optic circuits is limited by the electronics at the ends of the fiber more than the fiber itself. The maximum speed of data transmission is limited by the frequency of the underlying carrier. As one of my physics professors often joked "You can't play a pitsicato on a tuba!".

Fiber optic lines use a light beam to transmit data through the fiber. Ligth waves oscillate at over a million gigahertz.

On campus, the fiber channels transmit at 100megahertz or about 1 ten-millionth of the theoretical maximum speed of the channel.
Nationally, companies can now reliably transmit at 1 gigahertz over fiber, which is still about 1 millionth of the maximum.

Thus, the medium itself remains far faster than the electronics needed to send and receive at these increadibly fast rates. The College can expect to see continued growth in network speed as researchers perfect the technology.

Terabit networking:

Scientists at Lucent's Bell Labs have set a new record for transmitting data over fiber-optic cable by moving 3.28 terabits per second of data over 300 kilometers of Lucent's TrueWave optical fiber. At this rate, Lucent's fiber in one second could transmit three times the volume of daily Internet traffic for the whole world. Within years, fiber-optic cable could move tens of thousands of terabits per second of data. This tremendous bandwidth growth will be fueled by the speed of lasers used to encode data and the number of wavelengths a single fiber can carry at once, says AT&T Labs President David Nagel. Researchers are now developing terabit lasers, and the number of pulses a single laser produces is doubling every 18 months. In addition, the number of wavelengths a single fiber can carry at one time is doubling every year. Eighty-wavelength systems are already available, and scientists are working on 1,000-wavelength systems. The Bell Labs' record accounts for less than half a percent of the potential capacity of current optical networks, according to Kerry Vahala, professor of applied physics at the California Institute of Technology. (Wired News, 21 March 2000)

Summary from EDUCAUSE EDUPAGE (3/24/00)