LSI Logic Corporation announced today that a prototype of their first SAS (serial attached SCSI) switch will be on display at Storage Networking World Spring in San Diego.
The switch has nine connectors each grouping 4 SAS ports, and can be used to create a network of servers and storage devices. SAS switches are expected to offer a more affordable alternative to FC for short distance connectivity.
"A SAS copper cable has a distance limitation of 8 meters, which still makes possible building storage networks with a 16 meters diameter" suggests Charlie Kraus director of the HBA business unit at LSI Logic.
Another limitation of SAS switching when compared to FC is the total number of ports.
"A fully non blocking crossbar is at the heart of our product" says Kraus - "but right now is a 36-port crossbar".
"The sweet spot[for the SAS switch] until crossbars with more ports become available is a dozen of servers and a handful of storage devices" Kraus suggests.
The switch supports port zoning and can be managed via command line and graphic interface. In the future, SAS switches should offer also address-based zoning, an area of the standard that is still being perfected by the T10 Committee.
Similarly to FC, SAS switches can be cascaded. Test conducted by LSI Logic with 8-level deep cascades have shown negligible latency, according to Kraus.
SAS switches can also create redundant network configuration with storage devices and servers connecting to both switches in pair.
LSI Logic should begin shipping SAS switches in Q3. Pricing was not disclosed in today's announcement.
Posted by Mario Apicella on March 30, 2006 07:14 AM
