Yes, funnily enough Microsofts reason was not HFT but AI. Essentially inter-datacentre training is limited by latency between the datacentres.
Generally they want to build the datacentres close to metro areas, by using hollow core fibre the radius of where to place the data centres has essentially increased by 3/2. This significantly reduces land acquisition costs, and supposedly MS has already made back the acquisition cost for Lumenisity, through those savings.
That feels somewhat implausible. I assume a Microsoft sized data center starts at over $100 million. Moving the footprint X miles away might be cheaper, but is probably a drop in the bucket given everything else required for a build out. I would further assume that they were already some distance away from the top tier expensive real estate to accommodate the size of the facility.
Its reality. Its generally about site and infra access, including power and fiber paths. The bigger providers (eg AWS) simply dont have more feasible sites that are within a few ms of the existing region DCs. Expect to see more infrastructure like “local zones” or AZs that are tens of ms away from the rest of the region.
Generally they want to build the datacentres close to metro areas, by using hollow core fibre the radius of where to place the data centres has essentially increased by 3/2. This significantly reduces land acquisition costs, and supposedly MS has already made back the acquisition cost for Lumenisity, through those savings.