Elastic optical networking: a new dawn for the optical layer?

TLDR

Optical networks are evolving from simple on‑off modulation to sophisticated high‑speed schemes, driven by traffic growth and unpredictable content‑provider models, and the fixed wavelength grid is becoming a bottleneck, prompting a shift toward a flexible grid and elastic optical networking. The article aims to describe the drivers, building blocks, architecture, and enabling technologies of elastic optical networking, including early standardization efforts. It outlines the architectural framework and key enabling technologies that support the elastic optical networking paradigm.

Abstract

Optical networks are undergoing significant changes, fueled by the exponential growth of traffic due to multimedia services and by the increased uncertainty in predicting the sources of this traffic due to the ever changing models of content providers over the Internet. The change has already begun: simple on-off modulation of signals, which was adequate for bit rates up to 10 Gb/s, has given way to much more sophisticated modulation schemes for 100 Gb/s and beyond. The next bottleneck is the 10-year-old division of the optical spectrum into a fixed "wavelength grid," which will no longer work for 400 Gb/s and above, heralding the need for a more flexible grid. Once both transceivers and switches become flexible, a whole new elastic optical networking paradigm is born. In this article we describe the drivers, building blocks, architecture, and enabling technologies for this new paradigm, as well as early standardization efforts.