Who makes dci / coherent optics for AI data centers

DCI and coherent optics extend the network beyond the fiber and connectors of 3.11 that serve a single data hall, linking separate buildings on an AI campus or connecting sites across a metro area. This is a distinct technology from the direct-detect optics used inside a data hall (3.04): coherent transmission encodes more information per wavelength to cover longer distances, and the vendor base for coherent systems overlaps only partly with the vendor base for short-reach transceivers. As AI campuses grow beyond a single building and hyperscalers link multiple sites into one logical training cluster, demand for campus-to-campus and metro-scale coherent capacity grows with them. An investor should watch supplier concentration here separately from the rest of the optics stack, since coherent DCI has historically been a smaller, more specialized market than short-reach data center optics.