Most organizations, whether a small business or a department at a big company, need more disk storage. Even when IT budgets remain flat or decrease, storage needs can double every 18 months. Users never can find that delete key; with lower storage costs, it seems smarter to keep most files rather than delete them.
But all disk storage is not created equal. A small company or departmental workgroup often needs plentiful shared, but not highly secured, storage. For a small company, stepping up to a file server, usually powered by a Microsoft operating system, can represent a substantial capital and ongoing maintenance investment. While the security and application support often makes sense, groups that just need extra storage should look in a new direction: the network attached storage (NAS) appliance.
Some of the smaller units look like an external USB drive on steroids, and that's essentially what they are. Others are toaster size — either two- or four-slice, depending on how many disks are inside. Enterprise-level NAS systems generally are specialized high-throughput servers and are larger and more expensive than what’s needed by most small businesses. Imagine your external USB hard drive with two or more disk drives inside, and a network connection in place of the USB port, and there you have it.
Prices range from $225 to $300 for a dual-disk system that contains two 1 terabyte disk drives (if one fails, your data is still safe) to as much as $1,200 for boxes with five 1TB drives. I strongly recommend the boxes with five drives rather than two. The five-drive (RAID-5) technology provides faster disk access than a pair of drives, and these systems usually have one or more gigabit Ethernet connections for better throughput.
Several well-known manufacturers produce these systems, including Buffalo , Cisco Systems , Iomega , LaCie , Netgear , QNAP , Seagate  and Western Digital . These desktop units are quiet (unlike the rack-mountable systems), unobtrusive and hold from 2TB to 8TB of data.
Simple and Secure
Like their more expensive big-brother file servers, NAS appliances  make it easy to create shared volumes that everyone can use, with private areas for each user. If you already have a Windows file server, the NAS unit can be integrated with Active Directory and create profiles for the users you select. If you are buying a NAS system alone, you will have to spend, at most, five minutes setting up the system for shared access and about one minute setting up each user's private storage area.
Security controls are not as strong as those on a Windows server, but they still keep user areas very private. You can even set up separate volumes on one box and have public spaces on each volume that are available only to the users of that volume. It sounds odd that you can make public shared storage spaces private, but you can.
Some vendors even offer a great offsite backup option: They will replicate data from one NAS unit to another over the Internet (though this may require an additional license). Put one box in your office, back it up to a second box at home and — bingo! — you have disaster recovery compliance.
Don't misunderstand: A NAS unit is as good a file server as many groups need, but they will not support websites, e-mail servers or SQL databases. If you need an application server that also provides terabytes of shared file storage space, shop for a file server. But if you just need terabytes of shared storage space and want to keep your purchase price and management headaches low, take a good look at the many options in the world of NAS appliances.