Network Attached Storage(NAS) :
The NAS is stands for Network Attached Storage. NAS appliances work as pure file servers which are controlled by their own integrated network operating system. The memory is organised through file sharing, meaning that access to data is only possible at file system level.
Storage Area Networks(SAN) :
SAN stands for Storage Area Network. It also includes iSCSI. SAN is the technology which sometimes is also referred to as IPSAN or Storage over IP for storage networks, dictates the operation of direct storage protocols natively via IP. It works by encapsulating SCSI data into TCP/IP packets and transporting them via IP networks. Then an SCSI router transports the encapsulated SCSI commands to the corresponding target system based on existing mapping tables. This way, without setting up separate storage devices, iSCSI allows access to the storage network via a virtual end-to-end connection.
Topology Of SAN And NAS :
Some important Features Of NAS:
1.Those PC who can connect with LAN(or is interconnected to the LAN through a WAN) they permit NFS, CIFS or HTTP protocol to connect to a NAS and share files.
2.NAS recognize the data with the help of file name and byte balance, move file meta-data and also manage security, user verification, file locking.
3.NAS specifically permits information sharing between Unix and NT.
4.NAS head unit manage file system.
Some important Features of SAN :
1.Only when server class devices with SCSI Fibre Channel can connect to the SAN.
2. A SAN addresses data by disk block number and transfers raw disk blocks.
3.In case of SAN file sharing process is depends on OS.
4.In case of SAN File System is handle by servers.
Difference Between SAN And NAS: