10. Conclusion

We have just described the main factors that characterize signal propagation on a single-mode fiber. We have shown how, while attenuation was the only parameter considered in early systems, it became necessary to take into account more complex propagation phenomena as transmission rates, distances and injected powers increased.

In the course of this history of optical telecommunications, two types of fiber emerged for transmission at a wavelength of 1.55 μm: the so-called standard high-dispersion G 652 fiber and the dispersion-shifted G 653 fiber. The development of amplified systems and wavelength-division multiplexing, and the correlative growing importance of non-linear effects, have led to a review of the conclusions reached about dispersion-shifted fiber, and have established the hegemony of G 652 and derivative families, such as the latest-generation G 655...