By Dave Simpson
It may be an apples-to-oranges comparison, but Emulex last year shipped more Fibre Channel ports than all of the fabric switch vendors combined, and that includes Brocade, Cisco, and McData. Of course, Emulex’s switch ports are on embedded switch chips that reside inside storage subsystems such as disk arrays, whereas the other vendors sell external fabric switches.
Embedded Fibre Channel switches provide switching functions between disk drives and other components such as controllers.
Embedded switches attach to storage controllers and provide switching functions between internal disk drives and other components (see figure).
Recently, Emulex announced its next-generation FibreSpy SOC (switch-on-a-chip) 804, which runs at 4Gbps and is backward-compatible with 1Gbps and 2Gbps Fibre Channel. Production shipments to OEMs will begin in the next quarter (Emulex claims to have one OEM design win already), although end-user subsystems based on the chips aren’t expected until at least the second half of the year.
Within that time frame, Emulex may have a variety of competitors, but for now analysts point to Broadcom as a potential competitor.
Emulex’s chips are aimed primarily at two different applications:
- The Integrated SAN Switch (804E) provides front-end SAN switching within an array, potentially eliminating the need for external SAN switches (and management costs) in low-end applications, blade servers, and SMB environments; and
- The SuperScalar Tiered Storage (804S) theoretically enables thousands of Fibre Channel disk drives with mixed performance/capacity/price characteristics to be interconnected to provide tiered storage within a single array. This breaks the 126-device limit of the FC-AL protocol.
The Fibre Channel-only approach to tiered storage may lead to some controversy later this year because it provides an alternative to the much-vaunted approach of combining low-cost Serial ATA (SATA) drives and Serial Attached SCSI (SAS) drives to create single-system tiered storage. SATA-SAS combo systems are expected later this year.
“We’re providing for Fibre Channel what SAS and SATA have been promising, so OEMs can leverage their existing Fibre Channel infrastructure,” says Bob Brencic, Emulex’s senior director of switch marketing. “SAS-SATA tiered storage will be good for the low end, but for enterprise-class storage systems we think that tiered storage using just Fibre Channel makes more sense.”