Various Data Backup Media

By Author: James Walsh
Total Articles: 68
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This consequently increases the importance of data backup. But, one has to choose the backup media carefully. The choice of a data backup usually depends on:

Type of data
Relevance of data
Size of data

Various Media Backup Options

In order to choose wisely, one needs to firmly grasp the essentials of currently available common storage media. Basically, storage media can be classified into volatile and non-volatile media. Volatile media are those which depend on electricity - their functional life and ability depend on available power. Volatile storage media such as hard drives lose their electromagnetism consequently losing data. On the other hand, non-volatile media such as CD-R are very expensive and not frequently used as backup devices. These devices have the ability to retain or save data for a short time when the power connections are shut off. Non-volatile storage media allow users to work on data even when there is no power.

Most companies and personal users buy and use magnetic volatile storage media. Thus, they run the risk of data loss. The different types of magnetic ...
... storage media available are:

Floppy disks and Zip disks usually possess a shelf life of 10 years. But, these magnetic storage media depend on power and start losing their magnetic coating after five years. This means that they can only be used as effective backups for a finite period of three or five years. Floppy and zip disks require manual maintenance as they do not have any inlaid maintenance systems. The disks do not automatically verify data files and usually do not have any security mechanism. Thus, data stored on these disks is open to hacking and theft.
Hard disks boast of a working life of usually three or five years. Hard drives are typically used to archive data in industries. They require careful maintenance and handling. A popular derivation of the hard drive is the Jaz drive which allows reading and copying of the stored data using another hard drive. In short, the Jaz drive is a removable magnetic hard disk which has an inlaid security alarm system. The system provides for user convenience and data security. It reduces the risk of data corruption, in the sense that it allows the user to read and save the data on another drive. But Jaz drives are considered unreliable storage backup as they have a functional life of less than five years.
Tapes can be described as high-maintenance volatile storage media equipment. They need careful and controlled environment exposure i.e., tape drives are rendered useless when exposed to undue heat, light and humidity. In addition, the magnetic coating of the tape wears thin if used in excess. In other words, tape drives, though portable, cannot be used all the time as effective data backups. They need to be stored in a magnetically shielded environment such as a steel cabinet.
CD-ROM and DVD discs are being described as optical laser storage media. They have the ability to save, read and copy even minute data. Generally, CD-ROMs are non-volatile media and, thus, have a low risk of data loss. They are basically used to store data and make it available whenever needed. CD-ROMs are affordable and easily available. In contrast, DVD writers are not standardised, available and cheap to be considered for routine data storage functions. For data storage purposes, CD-ROMs can be either write-only or read-write, though longer term storage is normally done on write-only discs. These discs, usually labelled CD-R, are available in two types: green and gold. Artificial tests indicate that the green CDs have a storage life of 75 years and the gold ones boast of a working life of 100 years. Thus, it can be argued that the CD is a better storage magnetic medium. Read-write CD has a working life of more than 10 years enabling data to be re-written about 1000 times. CDs are considered highly reliable as their magnetic coating is designed to be immune to magnetic fields reducing the risk of data loss.
Magneto-Optic (MO) technology is the latest storage media invading data companies. It can be described as a hybrid read-write technology which provides longer, reliable storage than magnetic media.
Non-volatile Memory Devices technology has developed rapidly due to increased use of digital cameras. Digital cameras are now posing as a threat to CD-ROMs as reliable storage backup:
They are affordable and easily available
They have a high storage capacity
Their storage ability is not dependent on power

James Walsh is a freelance writer and copy editor. For more information on computer crime and Computer Forensics see http://www.fieldsassociates.co.uk