XAM Spec Shapes Up

The Storage Networking Industry Associations (SNIA) eXtensible Access Method (XAM) specification is gradually making its way down the path from theoretical concept to deployable technology.

A number of advances have occurred, but users will probably have to wait until 2009, at the earliest, before the technology will impact their organizations.

SNIA began working on XAM in 2005. The finishing touches are now being applied to the first release of the specification, software development kits are making their way to market, and support is growing.

Still on the docket are the development of conformance testing procedures and tools, incorporation of the standard into production storage products, and most importantly, endorsements from application vendors.

XAM is designed to address a long-standing problem. Storage vendors have used proprietary interfaces, such as EMC’s Celerra and NetApp’s Snap, to tag data, so it could be located when needed by applications or storage systems. This approach has meant that application developers have been forced to write to each of these interfaces, and generally data management systems could only work with their own information.Corporations wanted a more cohesive approach to storage management. The XAM Interface defines a standard API (Application Programming Interface), so applications and data management products rely on one interface to oversee fixed content information devices, such as SANs, NAS, and CAS. The potential benefits include improved product interoperability, an easier way to ensure information security, storage transparency, simpler long-term records retention, and more automation of Information Lifecycle Management (ILM)-based practices.

The first version of the standard is now making its way to committee members for their final approval, a process that should be completed by the summertime, according to Wayne Adams, treasurer and chair emeritus of SNIA’s Board of Directors.

In addition, the group has been building a software development kit -- the first software project initiated by the association -- that third parties can use to incorporate XAM support into their products. Also, storage vendors, such as EMC, HP, Sun Microsystems, and Vignette, have demonstrated prototype products designed to comply with the standard.

While there has been progress, several more steps need to be taken before users will benefit from the work. Once SNIA completes XAM 1.0, vendors will then need to add the feature to their products.

“There are some vendors already touting XAM compliance, but that is not possible until the standard is finished,” says Carolyn DiCenzo, research vice president at Gartner. ”If users deploy such products, there is a risk they will need to be upgraded once the standard is complete.”Storage vendors are putting time and effort into building XAM-compliant products, but the standard will only become useful when application vendors embrace it. “At the moment, there does not seem to be a lot of movement by application to endorse XAM,” said Laura DuBois, program director for storage software at IDC.

While SNIA has taken up development of the standard, it is a vendor consortium rather than a de jure standards body. Consequently, the organization plans to submit its specification to ANSI and ISO for accreditation, a process that will probably last until the middle of 2009. Sometimes, vendors tend to be cautious with emerging standards, so some may hold off incorporating XAM into their products until that time.

XAM has potential to ease the integration of data from different storage systems. While vendors have made progress in developing the standard, its benefits right now are more theoretical than implementable.

Have a comment on this story? Please click "Discuss" below. If you'd like to contact Byte and Switch's editors directly, send us a message.