The backup requirements of different people vary according to the quantity of data, type of data, time to take backups and the “resources” available to them. Finding one (or more) different plans can help one find the ideal backup.
The Data
If the amount of data to be backed up is large, certain options would not be viable. For example CD media can store less than 1 GB of data. Having to sit near a computer swapping countless disks will ensure that the first backup taken will probably be the last one.
Depending on the data, you can sometimes reduce its size by more than 50% by compressing it. Not all data compresses at the same rate. For example music, video and certain image files are natively compressed and will therefore not reduce in size much further. On an average mix of files, you should be able to expect around 33% reduction. By compressing files you might save a couple of media disks and the time necessary to write them. The downside of compressing data is that if one of the media disks fails, you might not be able to access the content held on the other disks.
The media
Optical Backup Media
- CD-R and CD-RW. These store less than a GB of data.
- DVD-R and DVD-RW. Can store 4.7GB of data.
- DVD-R and DVD-RW (DL). The media can store 8.7GB.
- Blu-ray BD-R and BD-RE media can store 25GB of data.
The media described are either write once or rewritable. The advantage of using CD and DVD—and in the future Blu-ray—media is that the backups are readable on drives by other manufacturers and on other systems. While write once media is cheaper than the rewritable equivalent, unless you need to archive data, in the medium term, backups on rewritable disks proove to be considerably cheaper than their write once equivalents. If you need to archive data, research the longivity of the media you want to write your archive data to.
USB flash memory solutions
Today one can find 64GB and greater USB drives for what one can consider a reasonable price. Like most of the media discussed above, the universal adoption of the USB standard makes it easy to read data created on one computer on others. Another advantage of flash memory over optical media is that flash memory is thousands of times faster than optical media.
Removable hard drives
This solution allows one to back up data running into the terabytes. Slower than flash memory, faster than optical media and bulkier than both, Removable hard drives store data on a magnetic stratum residing on a moving platter. Although today manufacturers are quoting that a drive’s average lifetime topples the 100 years, many studies are pointing out that failure rates are several times higher than reported by drive companies and therefore the figures being quoted should not be trusted. Another issue with removal hard drives is that these are susceptible to data corruption as a result of magnetic interference much more than the media mentioned earlier.
Tapes and other “specialised” backup media
Large companies/government bodies are normally the primary customers of these solutions. This is because tape based solutions—enhanced further through the use of hardware such as tape loaders—allow organisations to backup data that runs into the hundreds of terabytes without any human intervention. For SMEs (Small and Medium Enterprises) as well as home users, tape is no longer a cost effective and viable storage solution. This is because it is no longer the cheapest solution; it can be propriety; you will not find a tape drive on the computer at the next desk; being a sequential device it is slow to retrieve selected files and tape life is quite short compared to the other media.
Remote backups
This form of backup is unique in that the data is replicated to a physically different machine. While this could be the computer 1 metre to your right, it normally is a computer that is out of sight. Therefore if your office burns down or is destroyed after a storm causes havoc, you will not be looking through the charred remains for what was originally a USB stick. Remote backups are the least work because the solution can technically be designed so that you do not even have to remember to take a backup.
Whatever solution you opt for, do backup your data before you realise how much your data is worth.
