Indeed, Cisco acquired its way into iSCSI with the 2001 purchase of NuSpeed, an iSCSI router start-up. Cisco has since killed off the NuSpeed product, which was called the SN 5420.

"iSCSI we saw -- and it played out this way -- as more of a small-business play, where there was such a large entrenched base of FibreChannel that was projected by the analysts to continue to grow," says Jackie Ross, vice president of marketing in Cisco's Server Access and Virtualization Group. "We couldn't ignore that."

And iSCSI is even losing ground to network-attached storage (NAS) in the SMB market because SMBs are now opting for file-based storage -- which NAS supports -- vs. block-based storage, which iSCSI and FibreChannel support, Ross says.

"For SMBs, NAS -- or file-based storage -- has grown up as their needs have grown up," Ross says. "With some of the needs you could only get in block-based storage -- disaster recovery, much better management of multiple networks -- you can now get with file-based storage. That's the reason NAS has grown at double the rate of iSCSI."

But there's still healthy growth in iSCSI. It's growing at about 25% per year for companies that have not opted for NAS over direct-attached storage, Ross says.