Author: Cameron T Brett, Manager, Product Marketing
Enterprise and Storage Division,
Serial Attached SCSI (SAS) is now a mainstream technology for enterprise servers and storage. Evolving from parallel SCSI to a serial technology, SAS is much more capable than its parallel predecessor. SAS provides a roadmap to faster speeds and can create, and be managed as a fabric with the use of controllers, expanders and muxes. The standard today is 3Gb/s (300MB/s) across a SAS link. 6Gb/s SAS is coming and PMC-Sierra, an established storage technology provider of SAS, SATA and Fibre Channel solutions, is leading the way.
In 2007, PMC-Sierra announced two new 6Gb/s SAS controller products:
– PM8010 maxSAS SRC 8x6G – PCIe 2.0 to 8-port 6Gb/s SAS RAID Controller
– PM8000 Tachyon SPC 8x6G – PCIe 2.0 to 8-port 6Gb/s SAS Protocol Controller
Both products utilize 6Gb/s SERDES technology that was developed and hardened by PMC-Sierra over four years ago, which eliminates a key development effort when going from 3Gb/s to 6Gb/s.
PM8010 SRC 8x6G – PMC-Sierra’s 6Gb/s RAID-on-Chip (ROC)
The SRC 8x6G is the first 6Gb/s SAS product announced and sampling in the industry. It is targeted at enterprise servers requiring high-performance hardware RAID. With 6Gb/s SAS and PCIe 2.0, it provides investment protection as it offers backward compatibility with 3Gb/s and PCIe Gen1. From add-on RAID PCI-Express cards to RAID-on-Motherboards, the SRC 8x6G provides a platform for nearly all enterprise server RAID implementations.
The SRC 8x6G takes data protection to the next level. It includes data encryption to protect “data-in-flight,” as well as data-at-rest on the hard disk drive (HDD). The SRC works equally well with HDDs that provide their own encryption and HDDs that have no encryption capability.
T10’s Data Integrity Field (DIF) is a method of checking data as it travels throughout a system to ensure the integrity and accuracy of the data. This capability is built into the SRC 8x6G for high-performance data protection.
6Gb/s SAS, also referred to as SAS-2, brings added diagnostics to SAS eco-systems for better error checking and diagnosing problems. PMC-Sierra’s controller products take these diagnostics one step further by adding checks for better fault isolation within the chip, which can save OEMs and IT managers time and money by more effectively diagnosing where the true fault lies.
Figure 1: PM8010 SRC 8x6G ROC Application
SPC 8x6G – 6Gb/s SAS I/O Controller
PMC-Sierra’s SPC 8x6G I/O protocol controller is the first SAS product in the Tachyon family of storage products. Leveraging much of the same technology from the Tachyon Fibre Channel (FC) controllers, the SPC is ideally suited to enable enterprise storage system arrays.
Many current PMC-Sierra customers utilize the Tachyon family of FC controllers for their enterprise storage system products. As with any established product, a sizable effort is put into the software to ensure the products operate effectively in a storage system. For customers that are currently using Tachyon FC controllers and looking to offer SAS-based solutions, the SPC 8x6G shares the same software interface as the Tachyon FC controllers. This allows customers to seamlessly enable enterprise SAS/SATA disk drive support in their storage systems without investing in new software development.
Figure 2: PMC-Sierra’s 6Gb/s SAS Controller Products
The SRC and SPC controllers were recently demonstrated at Storage Networking World 2007 in Dallas, TX. Each demonstration showed functional operation in servers running video streams, performance tests and compatibility with 3Gb/s SAS and SATA disk drives.
The SRC 8x6G and the SPC 8x6G are sampling today to select customers for evaluation and are planned for production release in 2008.