Limitations and Perspectives of Optically Switched Interconnects for Large-scale Data Processing and Storage Systems

Abstract

The ever-growing Internet data traffic leads to a continuously increasing demand in both capacity and performance of large-scale Information and Communication (ICT) systems such as high-capacity routers and switches, large data centers, and supercomputers. Complex and spatially distributed multirack systems comprising a large number of data processing and storage modules with high-speed interfaces have already become reality. A consequence of this trend is that internal interconnection systems also become large and complex. Interconnection distances, total required number of cables, and power consumption increase rapidly with the increase in capacity, which can cause limitations in scalability of the whole system. This paper addresses requirements and limitations of intrasystem interconnects for application in large-scale data processing and storage systems. Various point-to-point and optically switched interconnection options are reviewed with regard to their potential to achieve large scalability while reducing power consumption.

Hybrid Optical Switching for Data Center Networks

“…According to [6] current data centers networks consume around 23% of the total IT power. When increasing the size of data centers to meet the high requirements of future cloud services and applications, the internal interconnection network will most likely become more complex and power consuming [7]. As a consequence, the design of more energy efficient data center networks is of utmost importance for the scope of building greener data centers.…”

“…When considering future data center requirements, optical switched interconnects that make use of optical switches and wavelength division multiplexing (WDM) technology can be employed to provide high communication bandwidth while reducing significantly the power consumption with respect to ptp solutions. It has been demonstrated in several research papers that solutions based on optical switching can improve both scalability and energy efficiency with respect to ptp interconnects [7,9,10]. As a result, several optical switched interconnect architectures for data centers have been recently presented [11][12][13][14][15][16][17][18][19][20].…”