Over the past 25 years, the evolution of the data center has been largely impacted by the pace of massive technological revolutions transforming the IT industry as a whole. Starting with the dot-com period to the cloud and virtualization era to today's Software-Defined Data Center Revolution, IT data centers have continually evolved. Moving from siloed architectures with dedicated systems to virtualized and cloud-based models that pool together compute, network and software resources, software-defined data centers are poised to increase business agility in the future.