Historically, Digital Realty has been a "wholesale" data center operator with a real estate focus, while Equinix has more technology DNA, as well as $7.5 billion of capital invested thus far to build out its interconnection focused "Platform Equinix."
What is the relationship between 'Equinix' and 'data center' in the context of the input sentence.
Options: distributed by, member of, employer, product/material produced