“We are still partnering with HP and IBM on the storage side,” Ravaswami says. “The Cisco/Brocade choice is dictated more by the end customer. I would not say that the bulk of the share loss this quarter was because of HP or IBM.”

Analysts and other observers also note that Cisco is very bullish on propagating , which replaces a FibreChannel switching fabric with Ethernet, yet still provides FibreChannel connectivity between servers and storage arrays. The T11 working group of INCITS/ANSI just signed off on the FCoE standard June 4, Cisco officials say.

Some observers have suggested that Cisco’s Q1 SAN numbers may be an indication that Cisco is cannibalizing its FibreChannel base in order to further its FCoE strategy.

“Cisco’s whole motivation is getting customers to adopt Ethernet infrastructure, not Fibre Channel,” says Deni Connor, principal analyst at Storage Strategies NOW. “Offering FCoE, which will ultimately allow its customers to shift from Fibre Channel to lossless Ethernet, is worth the risk of losing Fibre Channel share. You’ve seen Cisco do this in the past with its interest and support for iSCSI, which allows block-level storage protocols to run over Ethernet.”

Cisco says it is not sacrificing FibreChannel for FCoE because the two technologies address different applications and currently cannot easily replace one another. FCoE is a server-facing technology while FibreChannel is predominantly for attachment to storage arrays, the company says, which is why no MDS customers have replaced their SAN switches with the Nexus FCoE switch.