why we use san?


we use SAN  to store and protect data.
A SAN uses the SCSI(Small Computer storage Interconnect) and FC(Fibre Channel) protocols to move data over a network and store it directly to disk drives in block format.
In these days ,the high-speed network usually consists of fiber-optic cables and switches that use light waves to transmit data with a connection protocols known as Fiber-channel.


Well, What does a Protocol mean?


Protocol:A protocol is a set of rules used by the computer devices to define a common communication language.
IP(Internet protocol) based carporate networks,and even the Internet,are being used as the network part of a SAN.
Ip(Internet Protocol)Networks that are that are already in place can be used by other network connection protocols
such as iSCSI(inter-net Small computer storage Interconnect)to move and store the data.