On the use of intelligent metasurfaces in data centers

On-demand wireless links in hybrid data centers can augment the existing network capacity to improve the performance. In the absence of line of sight between the rack transceivers, reflectors have been considered in literature to support high bandwidth, on-demand wireless links within the data centers. Metasurfaces, as a candidate smart reflector technology can be harnessed to bring the intelligence burden to the reflector side which, coupled with the expected low power expenditure, can render the technology a useful alternative. Given the fact that this has not been considered in the literature before, in this paper we highlight the design challenges which emanate from such a consideration and present tools and methodologies which can be utilized to address these challenges, focusing on two problems: wireless link selection to be served by the metasurface, and workload characterization within the metasurface. The former is formulated as an optimization problem with demonstrated effectiveness in minimizing the job completion time. Moreover, the workload analysis reveals a number of interesting attributes, as for example, uneven spatial distribution of traffic on the metasurface's controller network and how this is affected by the metasurface size and location, while the use of beam splitting on the metasurface to support parallel processing and storage functionalities does not significantly affect the incurred workload. Unlike previous work on metasurfaces, which consider mobility-driven reconfigurations, in this paper for the first time we consider data-driven reconfigurations.