TABLE OF CONTENTS When vendors introduced the first RAID controllers into the PC server marketplace in 1989, their drive technology of choice initially was IDE. At the time, IDE was the best choice for several reasons. In the preceding section, I pointed out that the objective of RAID technology was to increase performance and reliability, but reduce cost. At the time, the SCSI standards were emerging and becoming solidified (the SCSI-1 specification was available). SCSI drives for the PC server market still did not provide a good balance between performance, reliability, and cost. Supplies of SCSI drives were not ramped up either. IDE drives, on the other hand, were in good supply due to their popular usage in desktop computers. As a result, vendors initially chose IDE technology for the first RAID controllers available. SCSI technology did not stay behind for long, however. Drive manufacturers and customers quickly began to pressure vendors to switch to SCSI-based RAID technology. This resulted in IDE being relegated to the desktop and portable computer market where we now see IDE (and evolutions of IDE such as Ultra DMA or Ultra ATA). As drive manufacturers quickly ramped up production and customers and vendors began demanding SCSI drives, SCSI technology quickly surpassed IDE, and SCSI-based RAID technology controllers began to emerge from the leading server vendors and third parties. Overall, SCSI provides many benefits over IDE, but these could not be realized until the early 1990s when vendors like...
