Server Storage Comparison
DAS – Direct-attached storage refers to a storage system directly attached to a server or workstation without a storage network in between.
NAS – Network Attach Storage provides both storage and a file system. NAS uses file-based protocols such as NFS (Network File System protocol, popular on UNIX systems) or SMB/CIFS (Server Message Block/Common Internet File System, used with MS Windows systems).
SAN – Storage Area Network provides only block-based storage and leaves file system concerns on the server. LUNs are displayed in MS Windows Disk Management as Physical Disk. Example of SAN protocols are Fibre Channel, iSCSI, or FCoE.