What is C3PO?
The C3PO research project, which stands for Colourless and Coolerless Components for Low Power Optical Networks, is seeking to address the issue of growing power consumption in optical networks.
To achieve this goal, C3PO is producing a new generation of photonic components, which are designed to be colourless and coolerless, resulting in greater energy efficiency, whilst still enabling bandwidth growth at an affordable price.
Who is taking part in C3PO?
C3PO is a European Commission funded research project, coordinated by University College Cork of the National University of Ireland. Participants in the consortium include Interuniversitair Micro-Elektronica Centrum of Belgium, CONSTELEX Technology Enablers of Greece, ADVA Optical Networking of Germany, Tyndall National Institute of Ireland, as well as CIP Photonics and POLATIS of the UK.
Why are colourless and coolerless photonics important?
With capacity demands growing exponentially, energy consumption is of increasing concern for telecommunications companies. According to C3PO, as capacity increases, power consumption increases super-linearly along with it. This is a necessary cost as optical lasers need to be kept at a controlled temperature to operate accurately. But as a result more power is used to cool optical networks than to run them. C3PO predicts that energy limits will constrain future growth and this will significantly slow down development of the “global knowledge economy”.
By using coolerless components large savings are possible. According to C3PO, a typical large modern internet data and switching centre with 5MWatt power consumption (44 gigawatt-hours a year) can achieve annual communications equipment and air conditioning power savings of up to four gigawatt-hours through the use of photonic components which operate without cooling. At a typical data centre this will reduce energy costs by €500,000 a year.
The colourless aspect of the technology refers to DWDM routers in which lasers must be finely tuned to operate effectively. C3PO is proposing changes in network architecture by adopting reflective modulators, which would be used to modulate the output of an untuned laser, which is less temperature dependent.
Colourless components are designed to be non-wavelength specific, which allows a single component type to operate at any wavelength in a DWDM system. This means that the technology can be universally applied from low-cost and reconfigurable router interfaces for metro networks, down to the end-user optical modems in FTTH/FTTB networks.
Where can the technology be applied?
Colourless and coolerless components can be applied in several areas, including: WDM-PONs, dynamic transport networks and mobile backhaul. C3PO is seeking to develop low-cost reflective photonic components for high capacity WDM-PONs. These are aimed at removing the need for thermoelectrically cooled tuneable lasers, which it is claimed will lead to global annual equipment savings of more than €300 million from data and switching centre applications. Savings would be achieved through the simplification of optical and electronic hardware, a reduced need for thermal management and the removal of manufacturing costs.
Dynamic transport networks are a focus area for C3PO, specifically in encouraging a shift in the way transport networks are designed and built. The project aims to exploit IP over DWDM architecture to solve issues related to cost, cooling, requirements and reconfigurability. This includes the development of a new generation of functional, high performance and power-efficient photonic integrated circuits (PICs) relying on the combination of reflective components and multi-wavelength laser modules.
Applications in mobile backhaul are also being considered despite C3PO being focussed on core and access networks. C3PO believes that it can apply the same fundamental photonic, electronic technology from “client to core” through the use of low-cost/high-speed reconfigurable optical links in a passive nature as a solution for mobile or wireless/wireline converged networks.
What are the challenges in creating these components?
The challenge in creating coolerless components involves the cooling requirements of Indium Phosphide, a semi-conductor used in high power and high frequency electronics. An interim step being considered by C3PO is to design semi-cooled components for Indium Phosphide which would operate at 40C to ease cooling requirements and reduce power dissipation. It is thought that alternative semi-conductors may be necessary for fully coolerless operation, and these are being researched in other projects funded alongside C3PO.