22 August 2001

If your data is valuable then you need a backup system. Computers and software can be replaced, but lost or damaged data is lost forever. A backup system is a necessity for most businesses.

Backup systems vary in capacity and speed and prices increases as capacity gets bigger and the speed gets faster. The main consideration for a business is how much data needs to be backed up. The following table shows the comparison of common types of backup systems, the cost includes five disks or tapes.

Type	Capacity	Cost	Cost per Mb
Zip Drive 100	100Mb	$550.00	$5.50
Zip Drive 250	250Mb	$700.00	$2.80
CD-Burner	650Mb	$565.00	$0.87
Travan Tape	10Gb	$1,295.00	$0.13
DDS Tape	12Gb upwards	$2,475.00	$0.21

The capacity of the different types of backup is based upon the native capacity. This is the capacity of the drive itself. Backup software compresses data and you can usually expect the compression to double the amount of data that can be saved. The actual compression depends upon the data, some files can be greatly compressed, some files actually get bigger if you try to compress them.

Zip Drives

Supplied by Iomega, Zip drives are a popular choice for smaller businesses and homes. They have the added advantage of being a substitute for floppy disks and are useful for transferring larger files. Zip drives come in 100Mb and 250Mb capacities. They can be external with parallel, USB or SCSI connections or they can be installed inside the computer with IDE, SCSI or floppy connections. They also come with backup software.

CD-Burners

Increasingly popular, burning CD's for backups are not the best choice as few come with backup software and the CD burning process is cumbersome. Their advantage is that CD's are portable and cheap, a blank CD is around $2.00 compared to zip disk at $30.00. CD burners are best installed internally on a computer with an IDE or SCSI connection. External CD burners are available and should only be bought in USB or SCSI format. Parallel port CD-Burners are generally a slow embarrassment and should only be bought for computers that don't have a USB capacity.

Travan Tapes

Travan standard tape drives are made by a number of suppliers and provide the best price per megabyte backup option. The current Travan standard, TR-5, has a 10Gb native capacity although the tapes and drives are often be marketed as 20Gb. There are external tape drives but they are best installed internally with IDE or SCSI connections. Before buying a tape unit make sure software is included with the unit.

DDS Tapes

Physically smaller than the Travans, DDS tapes look the same as a Super-8 video camera and DAT tapes. DDS tapes are common on higher-end servers and have native capacities of up to 40Gb. The common small business unit is 12Gb. Like Travan tapes, these are best installed internally.

Software

Software is important to backups as well. Windows comes with basic backup software included, although the versions before Windows 98 won't support tape drives and most backup programs will have trouble with CD-Writers. Zip drives come with their own backup software included although many people find the Windows software better. Cheaper tape drive units often don't come with their own software and rely upon the Windows software. The software that is included with good tape drives usually has better scheduling and reporting features than the Windows backup program.

The backup option you choose for your business must be able to save all your data in one backup. If you are having to switch disks or tapes mid-backup then it is more likely the backup won't get done or media will get mixed up. Backups need to be as simple as possible.