An improved telecommunications link is provided which includes a dispersion managed fiber with smoothly varying dispersion. The dispersion map may vary sinusoidally or as a sawtooth, for example. The smoothly varying dispersion works well for high data rate transmissions in a return to zero signal format. The dispersion managed fiber with smoothly varying dispersion may be formed by a wide variety of techniques. A method of forming dispersion managed fiber by localized heating or cooling is also provided.