Benefits Of Sas; Benefits Of The Fusion-Mpt Architecture - LSI LSISAS1068 Technical Manual

1.2 Benefits of SAS
1.3 Benefits of the Fusion-MPT Architecture
SAS is a serial, point-to-point, enterprise-level device interface that
leverages the proven SCSI protocol set. SAS is a convergence of the
advantages of SATA, SCSI, and FC, and is the future mainstay of the
enterprise and high-end workstation storage markets. SAS offers a
higher bandwidth per pin than parallel SCSI, and improves signal and
data integrity.
The SAS interface uses the proven SCSI command set to ensure reliable
data transfers, while providing the connectivity and flexibility of point-to-
point serial data transfers. The serial transmission of SCSI commands
eliminates clock skew challenges. The SAS interface provides improved
performance, simplified cabling, smaller connectors, lower pin count, and
lower power requirements when compared to parallel SCSI.
SAS controllers leverage a common electrical and physical connection
interface that is compatible with Serial ATA technology. The SAS and
SATA protocols use a thin, 7-wire connector instead of the 68-wire SCSI
cable or 26-wire ATA cable. The SAS/SATA connector and cable are
easier to manipulate, allow connections to smaller devices, and do not
inhibit airflow. The point-to-point SATA architecture eliminates inherent
difficulties created by the legacy ATA master-slave architecture, while
maintaining compatibility with existing ATA firmware.
The LSISAS1068 can function as an SSP initiator, an SSP target, an
SMP initiator, an STP initiator, or a SATA initiator. The LSISAS1068 uses
SSP to communicate with other SAS devices, and uses SMP to
communicate topology management information with other SAS devices.
STP communicates with SATA devices by tunneling through SAS
expanders directly to the SATA device or by using the SATA protocol to
communicate directly with the SATA device.
The Fusion-MPT architecture provides an open architecture that is ideal
for SAS, SATA, SCSI, Fibre Channel, and other emerging interfaces. The
I/O interface is interchangeable at the system and application level;
embedded software uses the same device interface for different bus
Benefits of SAS
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