Accurate emulation of fast optical circuit switches

Optical circuit switches (OCS) are emerging as a solution to the high bandwidth demands of data center networks. Recent research prototypes provide scalable bandwidth using a tenth or less of the power of an Electronic Packet Switch (EPS) and — unlike traditional OCSs — are able to provision point-to-point circuits in a few µs. The disadvantage of OCS is the lack of efficient buffers to store and process packets, requiring routing decisions (i.e. circuit scheduling) to be performed by an external controller. Thus, application performance using an optical data plane depends on the controller adopted. The problem is that exploring the technology to evaluate its advantages as well as comparing different controllers is a prohibitive task, restricted to few research groups. Fast OCS technology is still in its early stages, and studying the viability of its adoption requires building OCS prototypes, an expensive and time consuming solution. To address this problem we designed OCSEMU, a distributed emulation platform that mimics the behavior of fast OCSs using traditional packet switches. We show that OCSEMU achieves comparable performance to the state-of-the-art OCS prototype, providing the extensibility necessary to explore application performance and optimizations of emerging optical interconnects.