Architecture overview
Let's look at the architecture in detail in the following sections.
Conceptual design
The following figure illustrates the design at a high level for the customer:

Conceptual design (for DC)
Logical design
Software-defined storage logically extends the abilities that exist with compute resources to the storage infrastructure. Rather than using CPU or RAM reservations, limits, and shares, with software-defined storage, the administrator defines policies that are assigned to virtual machines and allows the characteristics of the storage to be defined and changed as business requirements change. Software-designed storage logical design is illustrated here:

Software-defined storage logical design
The software-defined storage architecture design addresses all the functional components of a solution that have an impact on the resulting logical designs in the environment.
Virtual SAN (vSAN)
vSphere has an embedded software-defined storage solution called vSAN in its hypervisor footprint...