Direct Drive Storage

Maximize digital data transfer.

Serial Attached SCSI (SAS) has become the de facto hard disk drive (HDD) standard for missioncritical applications. There are three types of SAS devices: initiators, targets, and expanders. Initiator devices include host bus adaptors (HBAs) and controllers. The initiator attaches to one or more targets, forming a SAS domain. Target devices include SAS hard disk drives (HDDs) or solid state drives (SSDs), SATA HDDs or SSDs, and SAS tape drives. Using expanders (low-cost, high-speed switches), you can increase the number of targets attached to an initiator to create a larger SAS domain.

Serial-attached SCSI is said to offer an ideal solution for businesses with substantial storage, backup and archiving demands. SAS is widely considered to be the prevalent interface for direct-attached storage and is used to support hard drive controllers in enterprise-grade server farms.

In the business enterprise, serial-attached SCSI is especially of interest for access to mass storage devices, particularly external hard drives and magnetic tape drives. SAS offers advantages over older parallel technologies. The cables are thinner, and the connectors are less bulky. Serial data transfer allows the use of longer cables than parallel data transfer. Problems related to crosstalk are less likely in serial interfaces than in parallel interfaces, because there are fewer conductors in the cables. The hardware for serial interfaces is less costly than the hardware for equivalent parallel interfaces.