HDD interface technologies
V Masakazu Kawamoto · Fujitsu Scientific and Technical Journal · 2006
The interfaces of hard disk drives (HDDs) have been changed to serial interfaces to meet the demands for high-speed data transfer. The main interfaces involved are the Fibre Channel (FC), Serial ATA (SATA), and Serial Attached SCSI (SAS). Up to now, the HDD market segments corresponded to the serial interfaces that were available. Because of the recent demands for cost reduction, however, requests are being made for serial interfaces optimized for the use of the HDD units. As a result, the HDD market segments have become fractionalized, and the correspondence between the market segments and serial interfaces has also been lost. For example, products in which a conventional low-end SATA and a large-capacity HDD are combined have begun to appear on the market as enterprise HDDs. This paper describes the features of these serial interfaces and the interface technologies of the HDD controller that enables serialization of the interfaces. It also discusses the technological problems of future HDD interfaces and their solutions.