The Serial ATA International Organization announced Tuesday the SATA Revision 2.5 Specification. The driving force behind the 2.5 revision is a consolidation of all the variations/additions made by various splinter groups since SATA's inception, as well as a number of feature upgrades that will make SATA more competitive with rival technologies, such as Serial Attached SCSI (SAS).

The key improvement seems to be "eSATA", which is a solution for connecting SATA drives outside of the computer case. We've seen a number of such implementations here in the lab on a number of motherboards, but it seems to be a fringe/specialty product. Standardization and full support of external SATA can only be a good thing. The solution has been likened to that of using an external USB hard drive -- except that it runs off a SATA interface directly.

The other improvements listed include "officialization" of a number of extensions made to the original SATA spec, such as NCQ, hot-plugging, and 3 Gbps support. Once chipset manufacturers implement SATA 2.5, you can expect official and seamless support of all of these technologies, as opposed to the mish-mash patchwork-quilt that SATA and its various extensions seem to be now.

Other new or improved features include two new cable and connector specifications, a port multiplier that allows users to turn one SATA port into multiple SATA ports, and a port selector—a SATA-based solution for high-availability data center applications that provides the ability to create redundant paths from hosts to storage devices without creating a single point of failure.

Although many of the features aren't completely new, but compiled from previous specifications or simply upgraded, consolidating everything into one specification makes it easier for designers and implementers to design products, said Marty Czekalski, interface architectures manager for Maxtor Corp., of Milpitas, Calif.

"It makes us less prone to errors, because we don't have to refer to various specifications to make sure there wasn't an errata issued to any part of the specification," he said.

Along with the SATA 2.5 specification announcement, SATA-IO released a separate specification for the Slimline Connector, a connector for swap bays on mobile PCs. The connector replaces the original SATA connector, which was slightly too large to fit into the existing envelop defined for the swap bays, Grimsrud said. The Slimline Connector specification will be rolled into the next iteration of the SATA specification, he said.

This just goes to show that new technologies never are fully mature and taken advantage of to the fullest until one or two major specification revisions. SATA 2.5 is looking good -- now the ball is in the court of the chipset and controller logic manufacturers. Let's hope they get it all right.