Optical communication links and networks are essential for the Internet backbone as well as for interconnects used in data centres and high-performance computing systems. Therefore, the energy consumption in optical transmission systems is an increasingly important problem within our information society. In 2010, the Internet and its data centres consumed 870 Billion kWh -- equivalent to the yearly output of 10 nuclear power reactors. If energy efficiency does not improve, and Internet traffic continues to grow at its current rate, then within eight years the Internet will consume more than twice the electricity produced globally today. In general, the energy needed to transport data will increase much more than the energy needed for its computation. The aim of this project is to tackle this growing problem with a multidisciplinary approach, combining expertise within photonics, electronics, and communication theory.
The focus of this project is the analysis of the trade-off between energy consumption, cost, and performance, based on the optical and electrical hardware, signal processing algorithms, system level design, and, most importantly, the joint optimization thereof. Not only is such an analysis unique within this field, it is also challenging in that it requires a cross-disciplinary approach. Our team is selected with this in mind and will provide the critical synergy. The outcome of this work will be a set of essential guidelines on how to design optical links and hardware with a given performance target, while minimizing the energy consumption. In addition, it will provide an understanding of the true bottlenecks in terms of energy consumption and point to areas where breakthroughs are needed. We address both long-haul transport systems (where performance is most significant) and short-haul interconnects (where cost is also very important, since each link is not shared among many users). The project will have an impact in academia (sharing knowledge through high-quality research publications), industry (through close industry collaboration), and society (by enabling sustainable growth of IT), and will highlight Sweden’s commitment and leadership for a sustainable future.
Using a two-stage process, and based on a cross-disciplinary approach, we will develop a new design methodology for communications links with focus on energy efficiency. We will develop novel power consumption models for electronics, optics, algorithms and emerging technologies, as well as demonstrating novel energy-efficient link building blocks. These will then come together in an activity that will perform the various trade-offs required to minimize the energy consumption of the given links. We aim at experimentally verifying full links that are 5 to 10 times more power efficient than today's state-of-the-art. Finally we will verify our models in challenging demonstrator projects, which will vertically integrate the optic, electronic and algorithmic components.