How does network-attached storage work?
Three general components are utilized in NAS configurations: standard hardware, specialized software, and data transfer protocols.
Dedicated NAS hardware, often called NAS box, NAS unit, NAS server, or NAS head, contains storage drives and disks, processors, network adapter, and memory (RAM). Together, these form the hardware component of a NAS unit which is where data will be stored and accessed via network-based communications.
Software is the key difference between a NAS unit and simply attaching a general server to a network to house and share files. First, NAS units use a paired down OS, which runs the NAS software that is typically embedded on the hardware to improve performance and security. A general purpose server operates standard OSes, with all its overhead, whereas a NAS unit only handles data storage and file sharing requests, greatly improving efficiency and performance.
The final component is the set of protocols that the NAS unit will be configured to use in connecting and transferring data across the network. Because NAS attach to TCP/IP networks, TCP/IP are the fundamental protocols for transferring data. TCP/IP rounds up packets of data, and then packages them with an address to be sent over the network.
Because when NAS units are connected to networks they can use a file-sharing protocol, they appear as file shares on workstations. File-sharing allows multiple users access to information and files as if it were on their own system. Each OS, Windows, Linux, and Apple, use a separate file system protocol for sharing:
- Network File System (NFS): Typical to linux and unix based systems, NFS is a vendor agnostic protocol, compatible with most hardware, operating systems, and networks.
- Common Internet File Sharing (CIFS)/Server Message Block (SMB): CIFS/SMB are windows specific protocols, which offer other features such as sharing printers.
- Apple Filing Protocol (AFP): AFP is Apple’s proprietary file sharing protocol, formerly known as AppleTalk.