A Tutorial on the emerging Flexible Optical Networking paradigm


Ioannis Tomkos
Athens Information Technology Center


Network traffic has consistently grown at an exponential rate and there is no indication that this relentless trend will cease. At present, the industry is hard-pressed to identify how future networks will continue to scale in capacity, while reducing the overall energy consumption and ensuring the economic viability of the deployed networks. It is understood that rigid fixed-grid wavelength division multiplexed (WDM) optical networks can no longer keep up with the emerging bandwidth-hungry and highly dynamic services. As the available spectrum in optical fibers becomes occupied and is approaching fundamental limits, the research community has focused on seeking more advanced optical transmission and networking solutions that utilize the available bandwidth more effectively. To this end, the spectrum and spatially flexible/elastic optical networking paradigm has emerged as a way to offer efficient use of the available optical resources.

In this talk we will try to provide a comprehensive view of the different pieces composing the "flexible networking puzzle" with special attention given to the occurring interactions between the different research fields. Starting from the physical layer technologies, possibilities to implement flexible transceivers and flexible optical switching operating on a flexible frequency grid will be presented. Subsequently we will discuss issues associated with the design, planning and optimization of spectrum and spatially flexible optical networks and at the end of the presentation we will highlight the latest developments around the control of such networks and the particular issues that arise during their operation. The associated challenges and future research directions for all pieces of the "flexible networking puzzle" will be revealed.