CertiGuide to A+ (Core Hardware)  9  Chapter 0110:  Removable Media

VI  ZIP Drives 1 Digital Audio Tape (DAT)

The bane of many PC technician and network administrators is the tape drive. Despite their poor performance, unreliability, and high difficulty of use, tape drives have become a necessary evil in the IT industry (let me tell you what I really think).

Tape drives provide a high capacity, inexpensive, and widely used media for backing up large amounts of data to a small, removable cartridge. They typically interface with a PC via a SCSI port, although lower end models can be used with a parallel port or floppy disk controller. The two most commonly used technologies of tape are:

• Quarter Inch Cartridge (QIC)
  
  
• Digital Audio Tape (DAT)

These tapes look like a scaled down version of the old reel-to-reel tapes that were used in large mainframe computers. The basic principle is that of a thin magnetic tape on which data is written from one end of the tape to the other. Data is written onto the tape in parallel tracks, usually 20 to 32 tracks that run the length of the tape.

A number of tape manufactures have come together to create the QIC committee. While consistently advancing the technology, the group has worked to keep a format common to all members to increase acceptance. The first QIC format was QIC-40. It was called this because it could back up 40 Megabytes of data. Later the QIC-80 was released.

As time evolved, 3M came out with the Travan series, which extended the QIC lifespan. Most Travan models can read QIC tapes.

VI  ZIP Drives 1 Digital Audio Tape (DAT)