WiCOD: Wireless control plane serving an all-optical data center

A novel architecture for the future data center networks with possibly up to a thousand of Top of the Rack (ToR) switches is proposed. The proposed architecture, WiCOD, relies on a wireless control plane serving an all-optical data plane. The first contribution of the work is the separation of the data and the control planes: while the data is switched between the ToR switches in an all-optical high rate network, the network state and control information is continuously conveyed to and from a central unit over an ultra low-latency wireless network. A proof of concept for this architecture is also presented by considering the initial design possibilities for each one of the planes. In order to obtain low packet delays, the data plane scheduling policies take non-zero reconfiguration and monitoring delays into consideration. The results prove that very low queueing delays are guaranteed for strictly frequent updates on the network state. Based on this observation, a technique for monitoring of ToR switch queue occupancy information is purposed. This monitoring technique uses mmWave wireless communications via a spatially adapted MIMO Orthogonal Frequency Division Multiple Access (MIMO-OFDMA) over a static frequency selective channel with large number of densely packed ToRs. The reduced monitoring delays, offered by this low-latency radio access technology, makes the fine-grained and adaptive circuit switching feasible and, in turn, enables a high utilization of optical switches.