LIGHTNESS: All-Optical SDN-enabled Intra-DCN with Optical Circuit and Packet Switching

Abstract

The proposed LIGHTNESS DCN architecture aims at a flat all-optical interconnection design by combining optical circuit switching (OCS) and optical packet switching (OPS) technologies. LIGHTNESS brings innovation into current data center networks (DCNs) through the introduction of a hybrid OCS/OPS data plane that drives nowadays’ multitier hierarchical architectures toward a flatter scheme for enhanced scalability, throughput, and latency. The design of the OPS node targets medium-port count (4 × 4 or 16 × 16) and low latency, which is operated for switching short-lived packet flows (also known as mice flows). On the other hand, the OCS node mainly handles long-lived data flows (known as elephant flows) and has much higher reconfiguration time than the OPS one. Transparent optical switching elements also bypass the use of expensive and power-hungry optical-electrical-optical (O/E/O) conversions and massive electrical cabling, improving the energy efficiency and cost efficiency of present EPS-only solutions. The introduced software-defined networking (SDN) control plane enables the virtualization of computing and network resources creating a virtual data center (VDC) and virtual network functions (VNFs) on top of the data plane.