The software-defined data center (SDDC) is a trend that has been growing in importance for several years, driven in part by factors such as virtualization and cloud computing. Infrastructure has been evolving to be more dynamic and adaptable in order to serve a business requirement for greater agility. But what is an SDDC, and how do you get there from the systems in place now? A simple definition of an SDDC is that it is a data center where the entire infrastructure is configurable under software control. This does not mean just servers, but also the networking used to interconnect them and the storage resources available to service the needs of applications. As an example, look no further than the data centers operated by the large Internet companies such as Google, AWS and Facebook, which need to be able to respond to constantly shifting demands on resources from customers. These have set the pattern for other service providers and enterprises to follow.