Local storage
DSSV can use local storage, or remote storage and I believe the only requirement is for a Windows Server to recognise it as a HDD so it can be a local disk inside the server, attached via SAS or at the other end of a building via FC/iSCSI.
DSSV is only a single point of failure if you have a single server, with a single pool of accessible to it. Volumes are built in DSSV storage pools and can be (but do not have to be) mirrored between multiple nodes in the cluster. Volumes therefore live on multiple servers and multiple disks, similar to how VSAN / ScaleIO functions. Access to these volumes is Active / Active with each node housing a copy of the volume can be serving live IO. This keeps the IO inside the box and local to it (but again not required). IO does need to be replicated though and writes have to be acknowledge by all nodes mirroring the volume.
So for everyone saying they use a SAN for resiliency and DSSV node failure is a data loss situation is not understanding the concept of it virtualising physical storage with a properly configured DSSV implementation.