NAS actually started out in the enterprise before the technology migrated down to SMBs and consumers, and for much of their lifespan they've focused on filling the task for which they were created: file hosting, serving, and backup over the network. Initial SMB NAS offerings used relatively small amounts of RAM and low-power processors (often ARM-based) ran very lightweight operating systems. There was just enough software and computing horsepower on the typical NAS to enable it to do its job, and nothing more. NAS vendors competed on the basis of RAID features, protocol support, and ease-of-use.
More recently, though, thanks to Moore's Law, NAS devices have been blessed with an embarrassment of computing power riches. Powerful processors and memory modules have gotten so cheap that they no longer add very much to the price of the NAS hardware, so that the typical SMB-oriented NAS of 2009 has more horsepower than the typical business desktop of five years ago. This is way more horsepower than is needed to serve files, so NAS boxes have steadily begun to accrue new features via regularly released software updates.
Many NAS offerings in the range of $200 to $600 (sans drives) have a feature set that looks something like the following:
- A web-based interface that lets users with minimal networking skills fully administer the NAS
- Support for CIFS, AFP, FTP, rsync, iSCSI and other common file protocols used on Windows, Mac, and Linux networks.
- Streaming media services
- Web-based photo galleries
- Backup to USB drives and/or a cloud storage service
- Time Machine support (for Mac backups)
- Bittorrent client
- Ability to add new software via a plug-in architecture
- Print server support (for USB printers)
The above list, though extensive, is just the basics; individual NAS offerings will have many more features model-specific features, like IPTV camera support, volume-level encryption, Active Directory Services support, and so on.
Because the functions above, as varied as they are, are now essentially "basic" parts of NAS functionality, they all work very well on most NAS devices from top vendor brands. This makes the typical NAS a very good deal for almost any SMB or home office, regardless of the amount of data that it actually needs to host. Very few IT offerings can boast this much integrated functionality that actually works as advertised. So for SMBs who need some networked storage and who are looking for an alternative to the traditional (and expensive) file and print server, it's hard to go wrong with NAS, especially given all the added features.