Telecommunication networks before the 1990s were susceptible to electromagnetic interference and lacked stability. By replacing expensive and outdated copper wiring, fiber optic lines were the catalyst behind the rise of the internet and dot-com boom. In keeping with the 50th anniversary of Photonics Spectra and this month’s “Connected World” theme, the editors culled the archives for key advances in fiber optic communications that would help reshape the world in which we live today. Photonic Switching Secures Fiber Systems 1990-1994 The first photonic switching systems were introduced, increasing the stability of communication systems with low risk of connection loss. If damage was done to a fiber, switch systems would protect information by moving to a new fiber. Optical and electronic cross-connect networks operate with fiber systems to provide security by allowing the switching of signals to different fibers. Courtesy of AT&T Bell Laboratories, Photonics Spectra, February 1993. Fiber Amplifiers Enable High-Speed Data 1994-1997 Video-on-demand, streaming and multimedia services all depend upon the speedy retrieval and transfer of data. When erbium-doped fiber amplifiers were coupled with dense wavelength division multiplexing (DWDM), data transfer speeds increased from around 2.5 Gbps to about 100 Gbps. High-quality pulses became obtainable through new energy levels provided by the combination of amplifiers and fibers; increasing the quality of data pulses proved vital for creating high-speed networks. A diagram of Germany’s OPAL (Optical Access Line) system, one of the few ways that fiber in the loop (FITL) was integrated in the 1990s. ONU: optical network unit. Courtesy of Deutsche Telekom, Photonics Spectra, February 1995. First Fiber in the Loop Emerges in Europe Fiber in the loop (FITL) was first integrated into Germany’s networking systems in 1993, proving to be a disruptive innovation that attracted over 1.2 million consumers in Germany by the start of 1995. The new fiber system expanded pre-existing networks, and served as a platform for the introduction of multimedia services. Mode-locked fiber lasers produce high-quality, stable pulses with the use of an erbium-doped fiber amplifier. Courtesy of Proc. OFC., Photonics Spectra, May 1995. Advances in Fiber Dispersion Profile 1997-2002 Fiber systems provided nondegradable connection and premium data rates about 10 times faster than copper wiring. However, the installation and manufacturing of fibers require highly educated workers, making it a more expensive investment. Thus the development of fiber optic systems would have to be cost-effective, stressing the importance of upgradability and a dispersion profile sufficient for various applications. Multimode, single-mode or even more complex dispersion fibers fill different roles within telecommunications, causing fiber selection to be a central element of fiber system cost. An elegant dispersion-managed fiber technology that proved its worth within submarine networks. Courtesy of Corning Inc., Photonics Spectra, January 2002. As thin as human hair, glass fibers are able to transport light through themselves as a means for transfering data.