NAS – Network Attached Storage, to make it simple, is a kind of storage device in computer science that provides local area network (LAN) nodes with file-based shared storage through a standard Ethernet connection. NAS is defined as a special kind of file-level data storage server, including storage devices (such as disk arrays, CD/DVD drives, tape drives, or removable storage medium) and embedded system software, and can support cross-platform file sharing.
A NAS is high-capacity storage that connects to your home or office network so that you and other users you designate can access your files from mobile devices and PCs without plugging in to the drive.
Usually NAS possess their own nodes on a LAN, and allows the user to access the data on the Internet without the intervention of the application server. The NAS device does not need to be located within the server but can exist in a LAN and can be made up of multiple networked NAS devices, attached to a local area network (typically, an Ethernet network) and assigned an IP address. In this configuration, NAS makes integrate all the data on the web for centralized management, and will reduce workload from the application or enterprise servers, which effectively reduce the total cost of ownership and protect the user investment. Lower requirement to the server that greatly reduces the cost of the server, and is conducive for high performance storage system in the popularization and application within a wider scope.
NAS uses file-based protocols such as NFS (popular on UNIX systems), SMB/CIFS (Server Message Block/Common Internet File System) (used with MS Windows systems), AFP (used with Apple Macintosh computers), or NCP (used with OES and Novell NetWare). NAS units rarely limit clients to a single protocol and can support various operating systems. Through any workstations, users can use IE or Netscape browser to intuitively and conveniently manage NAS devices. Thus, for question “are management features available on a NAS device?” The answer is “Yes!”
Simply, it is a file-level data storage server. It is used in LAN environment for a lot of host computers to share storage space and offer file sharing services. All its functions can be divided into five aspects:
Specially, for the second function, you may rely on some data backup software like AOMEI Backupper to back up your crucial data to NAS.
The reason why NAS can gain great popularity among home and small-size enterprise users is that it has lots of advantages over traditional storage devices:
However, just as ever coin has two sides, though NAS has a lot of brilliant features, it still has some disadvantages. Network attached hard drive transfers storage tasks to network by parallel SCSI. Thus, LAN has to handle not only stream from common end users, but also requests (including backup operations) from storage disks.
Data storage stream transfers through general network. Therefore, data storage will be influenced by other transportation within the network. When there are other big streams within the network, the system will be greatly decreased. Also, the data is vulnerable to be leaked out and etc. security problems.
Another disadvantages is that we can only access the data in NAS based on file level instead of directly access physical data. This will gravely affect system efficiency in some situations. Thus, big database can’t make use of NAS.
This article only picks import parts of the definition to NAS. For more complete and detailed information, you can search on Google or find it in Wikipedia.