Mosaic: Breaking the Optics versus Copper Trade-off with a Wide-and-Slow Architecture and MicroLEDs#

Kaoutar Benyahya et al. (Microsoft Research / Microsoft Azure)

Why: Link reach/power/reliability is the binding constraint on future DC fabric scaling; this directly targets the copper-vs-optics wall the PM cares about.

What: A new link technology that abandons the few-high-speed-channels model for hundreds of parallel low-speed channels, claiming copper-beating reach at up to 69% lower power and better reliability than current optics.

How: "Wide-and-slow" spatial multiplexing using directly-modulated microLEDs (not lasers) over massively multi-core imaging fibers, eliminating laser drivers and complex electronics; prototype shows 100 channels × 2Gbps scaling toward 800Gbps+ at up to 50m.

Where applicable: Protocol-agnostic and designed to drop in without server/switch changes — broadly applicable in principle, but still a research prototype, not a shipping transceiver.