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NAS Hardware.

Network Attached Storage hardware may be referred to as a NAS box, NAS unit, NAS server, or NAS head (depending on whom you ask). The server itself is essentially configured with storage disks or drives, processors, and random-access memory (RAM)—much like any other server. A NAS unit may be configured with more RAM, and the drive types and capacity may be similarly configured to meet the needs of specified use. But the main differences between NAS and general-purpose server storage lie in the software.


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NAS Software.

A NAS box includes software that’s deployed on a stripped-down operating system, usually embedded in the hardware. Compare that to a general-purpose server that uses a full-fledged operating system—sending and receiving hundreds or thousands of small, unique requests every second. By contrast, a NAS operating system takes care of just 2 things: data storage and file sharing.

Protocols

A NAS box is formatted with data transfer protocols, which are standard ways of sending data between devices. These protocols can be accessed by clients through a network switch, which is a central server that connects to everything and routes requests. Data transfer protocols basically let you access another computer’s files as if they were your own.
Networks can run multiple data transfer protocols, but 2 are fundamental to most networks: the internet protocol (IP) and the transmission control protocol (TCP). TCP combines data into packets before they’re sent through an IP. Think about TCP packets as compressed zip files and IP as email addresses. If your grandparents aren’t on social media and don’t have access to your personal cloud, you have to send them vacation photos via email. Instead of sending those photos 1-by-1, you can bundle them into zip files and send them over a few at a time. In a similar fashion, TCP combines files into packets before they’re sent across a network via IPs.
The files transferred across the protocols can be formatted as:

  • Network File Systems (NFS): This protocol is regularly used on Linux and UNIX systems. As a vendor-agnostic protocol, NFS works on any hardware, operating system, or network architecture.

  • Server Message Blocks (SMB): Most systems that use SMB run Microsoft Windows, where it’s known as “Microsoft Windows Network.” SMB developed from the common internet file sharing (CIFS) protocol, which is why you might see it referred to as the CIFS/SMB protocol.

  • Apple filing protocol (AFP): A proprietary protocol for Apple devices running macOS.