CertiGuide to Security+  9  Chapter 3:  Infrastructure Security (Domain 3.0; 20%)       9  3.2  Media            9  3.2.4  Removable Media

3.2.4  Removable Media 1 2 3 3.2.4.2  CD-R (Compact Disc Recordable)

Tape is the traditional high-volume backup media. It has historically had the advantage of providing the most storage for the least cost, at an acceptable (though not incredible) speed. Because of its ability to hold large amounts of material, it was also often used prior to the popularity of CD-ROM technology, for the distribution of software or data from one organization to another.

When choosing a type of media and removable media drive, consider the duty cycle of the equipment (how many hours’ use it can take per month/year), the life of the media (some media will last a couple years, others will last decades) and your backup needs so that you neither over buy (going for an expensive solution that’s more than you need) or under buy (and end up replacing your drive every 3 months, and tending backups for hours each night).

The drive and media manufacturers are the best source of this information. Note that different brands of media, for the same type of drive, often have different lifetimes.

A characteristic that tape shares with most other magnetic media is that it can be rewritten. When you no longer need the information on the tape, you just reuse the tape and the old information is written over by new. As with other magnetic media, if you don’t want to overwrite the tape, but do want to erase the data on it, a large magnet (sometimes called a bulk eraser or de-gasser) can be used to disrupt the magnetic storage mechanism, effectively “erasing” the tape.

3.2.4  Removable Media 1 2 3 3.2.4.2  CD-R (Compact Disc Recordable)