HP AH226A HP 8 Internal Port SAS Controller and HP Multi-Port Internal SAS Con - Page 9

Controller Overview, Serial-Attached SCSI (SAS) Technology Description, Controller Description - core

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1 Controller Overview This chapter provides an overview of the SAS controller and its technology. This chapter includes the following topics: "Serial-Attached SCSI (SAS) Technology Description" (page 9) "Controller Description" (page 9) Serial-Attached SCSI (SAS) Technology Description Serial-attached SCSI (SAS) is a method for connecting computer peripheral devices that employs a serial (one bit at a time) means of digital data transfer over thin cables. The method is specified in the American National Standard Institute standard called Serial-attached SCSI (Small Computer System Interface), also known as ANSI/INCITS 376-2003. In enterprise computing, SAS is of particular interest for access to mass storage devices, particularly hard disks. Serial-attached SCSI offers the following advantages over older parallel SCSI 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. SAS offers data transfer rates in excess of 3 gigabits per second (Gb/s), with potential rates of 10 Gb/s or more. Serial-attached SCSI provides an ideal solution for businesses with substantial storage, backup, and archiving demands. Controller Description There are two internal SAS controller form factors, depending on the server model: • HP 8 Internal Port SAS Controller, a low-profile, 64-bit, 133-MHz PCI-X host bus adapter which is available only as a factory-integrated core I/O option in certain servers. • HP Multi-Port Internal SAS Controller, an embedded controller on the server motherboard. Both controllers are supported by the SerialSCSI-00 operating system driver bundle, and by utilities delivered in the CommonIO bundle. Both controllers have the same key features: • SAS data transfer rates of up to 3 Gb/s • Data protection through Integrated Mirror (RAID 1) Serial-Attached SCSI (SAS) Technology Description 9

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1 Controller Overview
This chapter provides an overview of the SAS controller and its technology. This chapter includes
the following topics:
“Serial-Attached SCSI (SAS) Technology Description” (page 9)
“Controller Description” (page 9)
Serial-Attached SCSI (SAS) Technology Description
Serial-attached SCSI (SAS) is a method for connecting computer peripheral devices that employs
a serial (one bit at a time) means of digital data transfer over thin cables. The method is specified
in the American National Standard Institute standard called
Serial-attached SCSI (Small Computer
System Interface)
, also known as ANSI/INCITS 376-2003. In enterprise computing, SAS is of
particular interest for access to mass storage devices, particularly hard disks.
Serial-attached SCSI offers the following advantages over older parallel SCSI 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.
SAS offers data transfer rates in excess of 3 gigabits per second (Gb/s), with potential rates of 10
Gb/s or more. Serial-attached SCSI provides an ideal solution for businesses with substantial
storage, backup, and archiving demands.
Controller Description
There are two internal SAS controller form factors, depending on the server model:
HP 8 Internal Port SAS Controller, a low-profile, 64-bit, 133-MHz PCI-X host bus adapter
which is available only as a factory-integrated core I/O option in certain servers.
HP Multi-Port Internal SAS Controller, an embedded controller on the server motherboard.
Both controllers are supported by the SerialSCSI-00 operating system driver bundle, and by
utilities delivered in the CommonIO bundle.
Both controllers have the same key features:
SAS data transfer rates of up to 3 Gb/s
Data protection through Integrated Mirror (RAID 1)
Serial-Attached SCSI (SAS) Technology Description
9