Storage Networking Architectures
Comparing Solutions
NAS is different in that the File I/O request is extended over the LAN to a
centralized file system where the Block I/O conversion takes place. As
all file requests are extended to this one file system, NAS provides a
generic platform that provides not only networked storage access, but
also provides data sharing across heterogeneous hosts.
NAS architectures can be delivered either
in a standalone appliance where scalability is limited and no protection is
provided against device failure, or
as a gateway device that provides the benefits of NAS but with the
scalability and protection options of a SAN
DAS and SAN are both Block I/O based architectures
NAS is a File I/O based architecture