Network-Attached Storage is Much More Than an External Hard Drive

Network-Attached Storage is Much More Than an External Hard Drive – February 2009

If you find yourself running out of hard disk space, your first thought may be to add an external hard drive.  If you are not on a network, this may be a good choice.  Terabyte external hard drives are common and very inexpensive.  Installation is as easy as plugging it into a USB port on your computer and the additional drive shows up under My Computer.

If you are on a network, you may want to consider network-attached storage (NAS).  Unlike an external hard drive, everyone on the network can be given access to the storage.  Software is included that allows the space to be managed.  Folders can be password protected and a user’s rights can be restricted to viewing, modifying or deleting folders.  Users can also be given Read/Write, Read or no rights to a folder.  Backup software is also included.

A NAS device is actually a computer that has a processor and memory and several drive bays for hard drives.  It connects to the network with an Ethernet connection just like other computers on the network.

When choosing a NAS appliance, the first thing to look at is the drive size supported by the drive bays.  If you add the total space available on each drive, it will not give you the total space available for storage.  The total space available depends upon how many drives are installed and how they are formatted.

The formatting is referred to as the RAID level.  This acronym stands for Redundant Array of Inexpensive Disks.  The RAID level describes how data is replicated across many drives for the purpose or increasing data reliability and input/output speed.  It is important to know what RAID levels a NAS device supports and to talk to your consultant about the best configuration.  The RAID levels are as follows:

RAID 0 – distributes data over several disks to increase speed, but the loss of one disk means loss of all the data.

RAID 1 – this is also called disk mirroring as two or more disks store the same data.  If a disk is lost, the data is safe because it is stored on at least one other disk.  The total storage capacity is the size of a single disk in the array.

RAID 5 – combines three or more disks so that data can be recovered if one disk is lost.  The capacity of the array is reduced by the size of one disk.

RAID 6 – can recover from the loss of two disks.

RAID 10 – is a combination of RAID 1 plus RAID 0.

Most NAS devices support the ability to stream media to network clients or DLNA compliant devices.  DLNA (Digital Living Network Alliance) is a standard for moving movies, photos, music and other media between devices such as a NAS storage unit and a PS3, Xbox 360 or iPod.  Some NAS devices support Bluetooth for wirelessly moving pictures from your cell phone to the storage unit.

An important consideration is the number of USB ports on the unit and their functionality.  Typically these ports can be used to add additional hard drives.  On some units they can also be used to add shared printers.

The price of storage has come way down.  In addition to storing your data, NAS can also be used to back up data.  Protecting your data with a reliable storage and backup system is critical.