Storage Networking Architectures
SNIA Layered View
DAS SAN NAS
We can further leverage the SNIA shared storage model in the positioning of
DAS, NAS & SAN.
By looking at the functions described in each layer, we can see that with
a DAS solution the majority of the work is done in the host and at the
File/Record layer. Once the File I/O to Block I/O conversion has taken
place do we cross the line into the Block Aggregation layer, which in this
case consists of a direct cable.
The same could be said of the SAN solution with the exception that the
direct cable has now been replaced with a network architecture which
consists of a transport layer that carries the Block I/O commands across
the network. This transport protocol can be provided by either Fibre
Channel or iSCSI, both of which can be used to build a SAN.