DVD-RAM transition is full-speed ahead

Emedia Professional, April, 1999 by Werner Glinka

The so-called "format war" in rewritable DVD really has been little more than a war of words. When it comes down to real products available today, supported by multiple manufacturers with a well-defined upgrade and compatibility roadmap, there was never even a fight. The transition to DVD-RAM as the leading general-purpose rewritable optical storage medium is well under way, and accelerating to full speed ahead.

A recent issue of this magazine summed up the status of DVD-RAM: "If low-cost, high-capacity, reasonably fast, local removable storage is what you want, then DVD-RAM is the way to go" (January 1999, p. 38). Since then, the availability of single-user upgrade kits and jukebox storage systems with DVD-RAM drives has grown monthly. Developers continue to increase the pace at which they qualify drives and media with applications ranging from network-attached storage servers to digital video editing software for desktop PCs.

With the development of both systems and applications support, 2.6GB DVD-RAM is carving out a strong position as a tool for personal and business desktop computing, and enterprise storage. And DVD Forum members are rapidly taking the next steps in DVD's evolution, which include shipping DVD-ROM drives that read DVD-RAM media and completing work on a higher capacity media standard.

Hitachi and other DVD Forum member companies are meeting the commitment to deliver DVD-ROM drives that read DVD-RAM media. Proliferation of these drives in new PCs and upgrade kits will enable simple distribution of content from producers to users on a rewritable medium that costs just a penny per megabyte. After a single-sided DVD-RAM disc is recorded, it's simply removed from its protective cartridge and inserted into a read-capable DVD-ROM drive. The disc can then be placed back into a cartridge--which protects the phase-change media from dust or accidental damage--for subsequent re-recording. Like any valuable data storage medium, bare discs should always be stored in a protective case to avoid accidental damage.

Development of 4.7GB DVD-RAM also is on schedule, with the draft specification released in January 1999. The wobbled land-and-groove format technique used in current DVD-RAM drives supports increased capacity through enhancement of the media structure and modified recording algorithms. After final member comments, the DVD Forum will publish the specification and submit it to international standards bodies.

In the evolutionary process of specification development, the DVD Forum has also responded to new user requirements. The newly defined DVD-RW format provides for sequential writing of data, making it useful to developers in mastering applications. With less robust defect management and a relatively small number of rewrite cycles, this format is not intended for general-purpose data storage and distribution. DVD-RAM media, on the other hand, incorporates advanced error correction and defect management features, and supports a minimum of 100,000 rewrite cycles.

Proposals for other new high-density removable media formats do make interesting news stories. But claims about the superiority of alternative formats based on slightly different recording approaches or entirely new technology are really nothing more than positioning statements, unsupported by any evidence. The simple facts are that the infrastructure systems and storage applications supporting DVD-RAM are growing rapidly, read-compatibility with DVD-ROM drives will enable practically unlimited data distribution, and the capacity improvements defined by the DVD Forum present a clear roadmap for the removable data storage standard of the next century.

Werner Glinka is senior marketing director of optical and multimedia products at Hitachi America, Ltd. For more information about Hitachi's line of DVD products, call 800/448-2244, or visit the company's Web site at http: //www.hitachi.com.