3. Comparisons of different back-up media
Media | Size | Example | Advantages | Disadvantages |
---|---|---|---|---|
CD-RW | 650 mb | Personal files or small systems | small and portable fairly inexpensive fast access to data |
fragile - can snap or be scratched relatively small storage capacity. could not be used to back up a network or large system |
DVD-RW | 4.7 Gb | Personal files or small systems | fairly large storage capacity inexpensive to purchase most PCs contain a DVD RW-drive |
do not work in CD drives can be damaged by breaking or scratching probably won't be large enough to back up a large system or network |
Flash memory | Up to 64 Gb | Personal files or small systems | easily portable hold large amount of data more reliable than floppy disks and less easily damaged than CDs or DVDs |
storage per megabyte is more expensive than many of the other media they can be easily lost the metal part can be easily snapped off |
Magnetic Tape | Over 100 Gb per tape | Personal system or Network | relatively cheap per megabyte of storage can store large amounts of data - usually the whole network can be set to back-up overnight |
serial access so can be quite slow to access data need special equipment to record and read the data on the tape |
External hard drive | Up to 3000 Gb | Personal data | robust storage device. cheapest storage per megabyte than the other media can back up a whole system or network |
need a method of connecting the hard disk to the computer fairly cumbersome to carry and store when compared to other media |
Online storage | Unlimited | Personal data | accessible from anywhere | could take a long time to download a large amount of data May take a long time to upload the data in the first place. security issues - need to be confident that your provider has adequate security procedures in place can be an expensive method of backing up data. |