NAS
Network Attached Storage (NAS)
NAS systems, or network-attached storage, are devices that provide file systems and storage space to one or more clients over a network. They function as file servers, but most NAS devices can do much more. Besides the obvious advantage of allowing multiple computers to access the same data, NAS systems offer other interesting possibilities. Client computers can forego larger mass storage, enabling the use of silent SSDs while relegating noisier hard drives to the NAS, where they won't be heard while working, enjoying movies, or playing games on the PC. Another advantage is that NAS devices consume significantly less power than a PC, making them ideal for running long downloads or uploads and making stored data available around the clock, even over the internet.
Different Devices for Different Requirements
There are many different NAS models, from very small models for home networks with only one or two hard drives to large enterprise NAS systems that can accommodate eight or more hard drives. However, NAS devices differ not only in the number of HDD bays.
- Hard Drive Bays: Besides the varying number of bays, there are devices with internally mounted HDDs and those with externally accessible, usually hot-swappable, bays. Most NAS systems accept 3.5- and 2.5-inch hard drives, though some particularly compact and efficient systems only accept 2.5-inch HDDs or SSDs.
- RAID Levels: NAS systems with more than one HDD bay typically offer RAID functionality. Simple devices can handle RAID 0 and 1, while systems with four bays usually support RAID 0+1/10. Higher-end devices often offer additional modes like RAID 5 and 6.
- Connections: A 1000Base-T Ethernet connection for Gigabit LAN is standard, but some devices offer additional connections, sometimes with link aggregation. Many NAS devices can also be expanded via USB mass storage or can serve as print servers through the USB connection.
- Hardware Specifications: NAS systems are essentially very compact embedded computers, so there are variations in CPU speed and RAM. Most models use ARM architecture, but some are equipped with x86 CPUs like the Intel Atom.
- Features: All NAS systems offer file server services with CIFS/SMB, FTP, and other protocols. Many also provide numerous additional features, such as automated backup functions, print and scan functions, P2P clients, and much more.