Cisco Cisco DWDM Transceiver Modules Livre blanc
White Paper
© 2008 Cisco Systems, Inc. All rights reserved. This document is Cisco Public Information.
Page 1 of 20
Fiber Types in Gigabit Optical Communications
Abstract
Fiber optic cables are the medium of choice in telecommunications infrastructure, enabling the
transmission of high-speed voice, video, and data traffic in enterprise and service provider
networks. Depending on the type of application and the reach to be achieved, various types of
fiber may be considered and deployed.
This paper describes the main characteristics of optical fiber in general, and the properties of
multimode and single-mode fiber (MMF and SMF) in particular.
Brief History of Optical Communications
Table 1.
The Optical Era
Date
Milestone
May 16, 1960
Theodore Maiman demonstrates first laser at Hughes Research Laboratories in Malibu
December 1960
Ali Javan makes first helium-neon laser at Bell Labs, the first laser to emit a steady beam
1962–63
Alec Reeves at Standard Telecommunications Laboratories in Harlow, United Kingdom, commissions a
group to study optical waveguide communications under Antoni E. Karbowiak. One system they study is
optical fiber.
group to study optical waveguide communications under Antoni E. Karbowiak. One system they study is
optical fiber.
Autumn 1962
Four groups nearly simultaneously make first semiconductor diode lasers, but they operate only pulsed
at liquid-nitrogen temperature. Robert N. Hall’s group at General Electric is first
at liquid-nitrogen temperature. Robert N. Hall’s group at General Electric is first
1963
Karbowiak proposes flexible thin-film waveguide
December 1964
Charles K. Kao takes over STL optical communication program when Karbowiak leaves to become
chair of electrical engineering at the University of New South Wales. Kao and George Hockham soon
abandon Karbowiak’s thin-film waveguide in favor of single-mode optical fiber
chair of electrical engineering at the University of New South Wales. Kao and George Hockham soon
abandon Karbowiak’s thin-film waveguide in favor of single-mode optical fiber
January 1966
Kao tells Institution of Electrical Engineers in London that fiber loss could be reduced below 20 decibels
per kilometer for inter-office communications
per kilometer for inter-office communications
April 1970
STL demonstrates fiber optic transmission at Physics Exhibition in London
Spring 1970
First continuous-wave room-temperature semiconductor lasers made in early May by Zhores Alferov’s
group at the Ioffe Physical Institute in Leningrad (now St. Petersburg) and on June 1 by Mort Panish
and Izuo Hayashi at Bell Labs
group at the Ioffe Physical Institute in Leningrad (now St. Petersburg) and on June 1 by Mort Panish
and Izuo Hayashi at Bell Labs
Summer 1970
Maurer, Donald Keck, Peter Schultz, and Frank Zimar at Corning develop a single-mode fiber with loss
of 17 dB/km at 633 nanometers by doping titanium into fiber core
of 17 dB/km at 633 nanometers by doping titanium into fiber core
Late Fall 1970
Charles Kao leaves STL to teach at Chinese University of Hong Kong; Murray Ramsay heads STL fiber
group
group
1971–1972
Unable to duplicate Corning’s low loss, Bell Labs, the University of Southampton, and CSIRO in
Australia experiment with liquid-core fibers
Australia experiment with liquid-core fibers
1971–1972
Focus shifts to graded-index fibers because single-mode offers few advantages and many problems at
850 nanometers
850 nanometers
June 1972
Maurer, Keck and Schultz make multimode germania-doped fiber with 4 decibel per kilometer loss and
much greater strength than titania-doped fiber
much greater strength than titania-doped fiber
Late 1972
STL modulates diode laser at 1 Gbit/s
1973
John MacChesney develops modified chemical vapor deposition process for fiber manufacture at Bell
Labs
Labs
Spring 1974
Bell Labs settles on graded-index fibers with 50 to 100 micrometer cores
June 1975
First commercial continuous-wave semiconductor laser operating at room temperature offered by Laser
Diode Labs
Diode Labs
Early 1976
Masaharu Horiguchi (NTT Ibaraki Lab) and Hiroshi Osanai (Fujikura Cable) make first fibers with low
loss – 0.47 decibel per kilometer – at long wavelengths, 1.2 micrometers
loss – 0.47 decibel per kilometer – at long wavelengths, 1.2 micrometers
Spring 1976
Lifetime of best laboratory lasers at Bell Labs reaches 100,000 hours (10 years) at room temperature