Enabling technologies for evolving flexible/elastic optical transmission and expected benefits from their introduction in the networks

Flexible optical networking is widely proposed today by major vendors and operators as a solution that offers smooth system upgradability towards Tb/s capacities and optimized use of network resources. Latest research and development efforts proposed a variety of multi-carrier signal transmission methods with significantly increased spectral efficiency, (compared to legacy WDM), allowing the transport of ultra-high capacity channels and the adaptive filling of wavelength channels according to the demands and the required performance on a link distance basis. These developments enable the flexible bandwidth utilization of the optical links but are limited to the point-to-point transport of data. The key network elements required to truly enable the realization of a flexible optical networking system are the flexible transceivers and flexible switching nodes capable to adaptively generate, receive add/drop and switch tributaries with variable bandwidth characteristics.