Storage technology clears key hurdle

By Stephen Shankland

A technology that promises to bridge the worlds of data storage and networking has passed a key point on its path to becoming a usable standard.

The Storage Networking Industry Association (SNIA) subgroup that led the creation of the technology, called iSCSI, has completed a final round of comments on the technology, the group said Wednesday.

As a result, companies now can start building iSCSI products. Only minor changes are required before the Internet Engineering Task Force (IETF) endorses iSCSI as a formal version 1.0 standard.

SCSI is a widely used standard for connecting hard drives to computers. iSCSI lets that happen over a network connection such as a company Ethernet network or even the internet. iSCSI holds the promise of letting multiple computers tap into a pool of storage systems.

iSCSI's main competitor is an existing technology called Fiber Channel, which is expensive and considered complicated, yet faster and better established than iSCSI. The new technology, though, can use existing computer networks where Fiber Channel requires separate equipment.

Fiber Channel is largely promoted by specialist companies such as Brocade Communications, while iSCSI piggybacks on the networking expertise and technology of mainstream companies.

Cisco Systems and IBM are among the biggest backers of iSCSI and have worked hard to develop it. The companies have even begun shipping products with early versions of iSCSI.

One of the hurdles for the technology's adoption was the IETF's requirement that iSCSI include support for a technology called IPsec, which permits encrypted communications. IPsec support threw a wrench in the works of companies such as Adaptec that planned to build special-purpose microprocessors that speed up the communications that underlie iSCSI.

"iSCSI chipsets will eventually include support for IPsec in them," said Doug Ingraham, senior manager for Cisco's SN 5400 line of iSCSI storage switches. In the meantime, Cisco will support iSCSI's IPsec by packaging it with a separate networking system, he said.

Some others are supporting the IPsec with software, a route that is sluggish compared to special-purpose chips but not necessarily that big a problem because customers aren't clamouring for IPsec at this point, Ingraham added.

Cisco recently began including Fiber Channel communication capabilities in its SN 5428 iSCSI switch. In August, Cisco introduced its MDS 9000 switch, a higher-end system that supports dozens of iSCSI and Fiber Channel ports.

Stephen Shankland writes for CNET News.com.