This article can also be found in the Premium Editorial Download "Storage magazine: Five cutting-edge storage technologies."
Download it now to read this article plus other related content.
|A quick look at some major storage standards|
What follows is a look at four storage-related standards: the Fabric Application Interface Standard (FAIS), Storage Management Interface Standard (SMI-S), RAID Data Disk Format (DDF) and iSCSI. The standards are presented in various stages of family unity, presented in rough order from the youngest to the oldest.
"There are always differences of opinion on any major standard," says Roger Reich, a member of the technical working group (TWG) responsible for SMI-S. "There are plenty of disagreements; that's part of the process."
All these disagreements can take a while to work out. For example, there were 20 distinct revisions of the iSCSI protocol before it got to a point where the entire membership of the Internet Engineering Task Force (IETF)--the guiding organization behind iSCSI--voted on it in April 2004. After four-plus years in the making, iSCSI is now officially considered a "proposed standard," meaning that the first version of the protocol is done. There will be additions and modifications in future versions, but the basics are set.
Generally, there are several pieces of any given standard. There's a core specification for iSCSI, for example, but there are also subsections related to security, naming, internationalization and other issues. Different members of subworking groups are generally responsible for those.
Then there's the matter of implementation. Many of today's standards require ensuring all of the resulting wares really do play nicely together, particularly because vendors are trying to get an early jump on incorporating them into products. As Gartner Inc. analyst Ken Dulaney explains, a standard doesn't necessarily "mean much to the end user until it is certified by an independent party. Without a certification body, there's liberty to implement it in many ways."
Of the standards profiled here, only SMI-S includes a separate product-certification effort to date, with plans to do so for RAID DDF-enabled products soon.
This was first published in October 2004