Architecting VMware vSAN 6.2 : vSAN Introduction : 2.3 vSAN Internal Architecture
   
2.3 vSAN Internal Architecture
One of the vSAN unique advantages is that the product runs as a kernel module within the vSphere hypervisor, as opposed to running as a virtual appliance on the host. This architecture is therefore able to provide far greater performance and better interaction with the hypervisor. The following diagram illustrates how the modules interact with one another.
The remainder of this section addresses each of these key architectural components and its role in the vSAN integrated architecture.
Figure 3. vSAN Hypervisor Integrated Architecture