Storage Area Network Solutions

 

   

 

In computing, a Storage Area Network (SAN) is an architecture to attach

remote computer storage devices (such as disk arrays, tape libraries and

optical jukeboxes) to servers in such a way that, to the operating system,

the devices appear as locally attached. Although cost and complexity are

dropping, as of 2007, SANs are still uncommon outside larger enterprises.

 

By contrast to a SAN, Network Attached Storage (NAS) uses file-based

protocols such as NFS or SMB/CIFS where it is clear that the storage is

remote, and computers request a portion of an abstract file rather than a

disk block.
 

Network types
 

Most storage networks use the SCSI protocol for communication between

servers and disk drive devices. However, they do not use SCSI low-level

physical interface (e.g. cables), as its bus topology is unsuitable for

networking. To form a network, a mapping layer is used to other low-level

protocols:

"iFCP" or "SANoIP" mapping SCSI over Fibre Channel Protocol (FCP) over IP.
 

iSCSI, mapping SCSI over TCP/IP.
 

iSER, mapping iSCSI over InfiniBand (IB).
 

HyperSCSI, mapping SCSI over Ethernet.
 

FICON mapping over Fibre Channel (used by mainframe computers).
 

ATA over Ethernet, mapping ATA over Ethernet.
 

Fibre Channel over Ethernet (http://open-fcoe.org/)