FCIA approves 4Gbps fabrics (but not unanimously)

Will switch vendors follow?

By Dave Simpson

Last week, the Fibre Channel Industry Association (FCIA) voted in approval of using 4Gbps Fibre Channel in switched SAN fabrics. Previously, 4Gbps Fibre Channel was to be limited to "inside the box" (e.g. disk drive and array) implementations, and 10Gbps was assumed to be the next speed for Fibre Channel fabrics.

According to Skip Jones, FCIA chair (and QLogic's director of planning and technology), about 2/3rds of the FCIA membership participated in the vote, with 60% voting in favor, 30% opposed, and 10% abstaining.

QLogic, the #2 vendor of Fibre Channel host bus adapters (HBAs) has been the most vocal proponent of 4Gbps at the fabric level. Last week, two other HBA vendors announced intentions to deliver 4Gbps HBAs--Agilent and JNI.

However, the leading vendor of Fibre Channel HBAs--Emulex--is not necessarily committed to delivering 4Gbps HBAs. Although Emulex is developing 4Gbps ASICs for embedded implementations and target devices, development of 4Gbps HBAs will depend on OEM demand, according to Mike Smith, executive vice president of worldwide marketing at Emulex.

"If our OEMs drive us to support 4Gbps on HBAs, we'll support it," says Smith, who notes that "up until recently, none of our OEMs were thinking about 4Gbps [at the fabric level]."

Emulex's wait-and-see stance is similar to the stance of the major Fibre Channel switch vendors. "We're investigating the need for 4Gbps with our OEM partners," says Tony DiCenzo, director of industry marketing at Brocade, the market share leader in Fibre Channel switches, "and right now there seems to be a limited need." DiCenzo says that OEMs are primarily concerned that development of 4Gbps products not impede development of 10Gbps Fibre Channel products.

"We're now developing around 1, 2 and 10Gbps, but our architecture does not preclude 4Gbps if the market should go that way," says Ed Chapman, senior director of product management in Cisco's storage technology group. "We have a wait-and-see approach; if our customers [end users and OEMs] ask for it, we'll provide it." Chapman says that he sees little OEM demand for 4Gbps Fibre Channel now, but that situation could change in a year or so.

McDATA, the leader in director-class Fibre Channel switches, seems more committed to the 4Gbps possibility. "We will introduce 4Gbps products, but we are not announcing any availability dates at this point," says Bob Williamsen, director of strategic marketing at McDATA. "We believe that 10Gbps products will be ready and deployed before 4Gbps products, and we don't see 4Gbps hurting 10Gbps adoption because they address different needs."

According to the FCIA's Jones, the key benefits of 4Gbps Fibre Channel at the SAN fabric level are:
--Twice the speed of 2Gbps Fibre Channel at about the same, or slightly higher, prices. (In contrast, 10Gbps Fibre Channel products are expected to cost 3x to 5x the price of 2Gbps Fibre Channel products, although estimates of 10Gbps pricing vary widely.)
--Full backward compatibility with 1Gbps and 2Gbps Fibre Channel. (In contrast, 10Gbps Fibre Channel will not be compatible with lower-speed products.)

Jones predicts that 4Gbps disk drives and HBAs will be available in sample quantities to OEMs by the end of this year, with production shipments coming around the middle of 2004. In Jones' opinion, 10Gbps Fibre Channel products will be available in approximately the same time frame.

But even Jones says that OEMs and end users will determine the need for 4Gbps Fibre Channel. "OEMs will have to decide if they want to go to 4Gbps, and users will have a lot of say in it too."

A more detailed report on this topic will appear in the July issue of InfoStor.

This article was originally published on June 11, 2003