Large Data Center Interconnects Employing Hybrid Optical Switching

Current data centers (DCs) networks rely on electronic switching and point-to-point interconnects. When considering future DC requirements, point-to-point interconnects will lead to poor network scalability and large power consumption. For this reason several optical switched interconnects for DCs have been recently proposed. However, the proposed optical switching solutions suffer from low flexibility and are not able to provide service differentiation. Furthermore, very few studies evaluate possible improvements in energy efficiency offered by optical switching solutions. In this paper we introduce a novel architecture of interconnects for DCs based on hybrid optical switching (HOS). HOS combines three different optical switching paradigms, namely circuit, burst and packet switching within the same network. Furthermore, HOS envisages the use a two parallel optical switches, a slow and low power consuming switch for the transmission of data using circuits and long bursts, and a fast switch for the transmission of packets and short bursts. The possibility of choosing between circuits, bursts and packets ensures the flexibility required by future DCs. At the same time, the option to select the most suitable switch technology for each data flow guarantees high transmission efficiency and low power consumption