RAID (Redundant Array of Inexpensive Drives) as a technology can look back on an illustrious career. Originally, only servers and prohibitively expensive workstations where equipped with such disk arrays, but nowadays, even low-cost mainboards support the two simplest RAID modes 0 and 1 - and with good reason. While hard disks have evolved over time, there is still always the danger of mechanical failure and the subsequent loss of all data on the drive. Also, even the most modern hard drives sometime represent bottlenecks for PCs.

It still takes a long time for data to arrive in the system's memory for hard-drive intensive applications. And when time is short, the 60 MB/s transfer rate that hard disks can sustain can make startup times of applications such as Photoshop seem like an eternity. One popular solution to this dilemma is the use of two or more hard drives in interleaving fashion. This is called RAID-0 or striping mode, and enhances performance. Controllers for this RAID mode are very inexpensive and can be found on many mainboards today. The trouble is that with every additional drive in this type of array, the risk of a mechanical failure increases - and if even one disk fails, the entire array becomes nothing more than a useless collection of bits and Bytes.

Arco leaves the task of finding an efficient and secure way to enhance drive subsystem performance to other companies.

The company's full name is, after all, Arco Data Protection Systems. It is no surprise, then, that both the EzCopy and the DupliDisk3 are based on RAID-1, which denotes a type of array in which the entire content of one drive is mirrored or duplicated onto another drive. Usually, this happens in real-time.

For example, a RAID controller recognizes the failure of a hard drive, alarms the mirroring software, which is ideally installed as well, and ensures continuous, problem-free and smooth operation of the system.

The DupliDisk3 is an add-in system for users who don't own a RAID controller but need or want the additional security offered by a RAID 1 setup - without having to reconfigure their Windows installation. More on this feature later in the article.

EzCopy uses similar RAID hardware, which is housed in an external, stand-alone case the size of a mini-barebone computer. It sports two drive bays for replicating the contents of one drive to another.