Archiving data to DVD

Despite many stumbling blocks, DVD may be poised to emerge as a viable data archiving medium.


The Digital Versatile Disc (DVD) market has been plagued by late deliveries, standards discord, and unrealized potential. With recent developments, however, all that may change. An upswing in market demand driven by standards and regulations, new economies of scale, and recent technological improvements are coming together to make DVD an attractive choice for data archiving, especially in two key vertical markets: finance and medical imaging.

DVD comes in two primary varieties: DVD-RAM and DVD-R. DVD-RAM is randomly rewritable, like a hard drive or floppy disk, making it a good choice for environments where data must be changed or deleted. DVD-R media, on the other hand, can only be written once, using specialized hardware and software. Thus, when it is necessary to certify that recorded information is unchanged, DVD-R is the better choice. Both DVD-RAM and DVD-R media can be read using the same techniques, using commonly available hardware. As of this writing, both can store 4.7GB on one piece of media.

Part of the impetus for use of DVD as an archival medium is its economy of scale. Like its predecessor, the compact disc (CD), DVD shares its genesis with the entertainment industry. Unlike CD, however, DVD has been designed for dual purposes-data and video -from the start, which means it has all the properties required of a digital data medium, while benefiting from the high volume and low costs associated with commodity devices and media.

The U.S. Securities and Exchange Commission (SEC) has long required that securities dealers retain records of transactions and correspondence. Originally, these records were kept on paper, but later on, microfilm was used to reduce the physical space required. Today, although many transactions still take place on paper, electronic transactions are increasingly prevalent, prompting the SEC to issue an amendment to its procedures, specifically, rule 17a-4, to allow records to be kept on electronic media. Similarly, the U.S. National Association of Securities Dealers (NASD) recently issued an amendment to its rule 3110(a) to provide that copies of correspondence be maintained in accordance with SEC regulations. Since correspondence is often electronic today, this means that archiving e-mail to electronic media is a natural solution.

SEC rule 17a-4 specifies that electronically archived records be kept in a "non-rewritable, non-erasable format that provides a permanent and unalterable record." The rule also requires that information "cannot be removed without detection." In conjunction with the appropriate storage management software, DVD-R media can be used to meet these requirements. Paper originals may be scanned, indexed, and archived to DVD-R media using a typical document management system, suitably modified to write to DVD-R. Copies of electronic originals may be similarly archived as part of a workflow process. Both processes involve fairly traditional uses of document imaging and archiving tools.

The most explosive growth in financial archiving is in the retention of electronic correspondence. E-mail is becoming the communication method of choice, as more and more securities dealers and customers are Internet-enabled. In fact, in many circles, paper correspondence may soon be a thing of the past. In a practical sense, the only way to meet the SEC and NASD requirements for permanent archiving of e-mail correspondence is through write-once digital media like DVD-R. This means that specialized storage management applications for transparently indexing and recording e-mail are needed.

DVD for medical

Like the financial industry, the medical industry has been moving away from traditional media, such as paper and film, to digital media. For example, imaging devices such as X-ray machines, CAT scanners, MRI machines, and ultrasound scanners can now record and output their information in digital format. Even without the obvious benefits that accrue from increased accessibility of digital information versus film, digital storage of medical information achieves cost saving by reducing the need for secured, climate-controlled warehouse space.

The emerging fields of telemedicine and teleradiology, in which medical information and diagnosis are available electronically over networks, are driving the growth of digital medical archiving systems. According to a BCC Communications research report, "Rooms full of X-ray film will eventually be changed to jukebox systems storing laser disks." The report goes on to say, "In addition to saving space, cost, and resources, the images stored optically in a computer-controlled jukebox cannot be misplaced, like X-ray films can."

The medical industry has been careful to create industry standards that allow input devices, storage systems, diagnostic services, and viewing stations to interoperate. The Digital Imaging and Communication in Medicine (DICOM) standard has been created through the cooperation of all major medical equipment manufacturers. DICOM is a standard that continues to evolve to accommodate new technology.

For example, proposed changes to the DICOM standard allow DVD-RAM and DVD-R media to be used as a storage medium in medical information systems. The DICOM committee's criteria for selecting DVD as a storage medium included interoperability, ubiquitous readability, high capacity (2GB to 5GB per disc), high performance (transfer rate greater than 2MBps), durability, broad availability, and economy of scale. DVD has all these qualities.

Unlike the financial industry, the medical industry considers DVD an interchange and archival medium. Interchange of DVD media is accomplished using a standard file system format known as Universal Data Format (UDF), which was created by the Optical Storage Technology Association as a fully compliant subset of an existing ISO standard (ISO-13346). Operating system vendors, platform manufacturers, and third-party ISVs have embraced UDF. In the future, UDF is expected to be the mechanism that allows DVD to achieve ubiquitous readability-an important component of the DICOM proposal.

The potential for market growth in DVD-related hardware, software, and services is only now being unlocked. In the financial industry, new regulations that require permanent archiving of electronic documents are driving an increase in the need for DVD-R. In the medical industry, emerging standards make it possible to use DVD-R and DVD-RAM as an archive and interchange medium. Both industries may benefit from DVD's broad acceptance, economies of scale, and new standards like UDF.

Barry Mattingly is VP of marketing at BakBone Software Inc. (www.bakbone.com) in San Diego, CA.

For more information...

"The Impact of Recent Technological Advances on the Securities Markets," U.S. Securities and Exchange Commission-www.sec.gov/news/studies/techrp97.htm.

"Reporting Requirements for Brokers or Dealers under the Securities Exchange Act of 1934," U.S. Securities and Exchange Commission-www.sec.gov.

NASD Manual and Notices to Members-NASD Regulation's Website, www.nasdr.com.

DICOM standards-National Electrical Manufacturers Association's Website, http://medical.nema.org.

UDF specifications-Optical Storage Technology Association's Website, www.osta.org.

"A Look Inside the U.S. Diagnostic Imaging Market," report from Business Communications Co. Inc.-www.devicelink.com/news/market5.html.

This article was originally published on February 01, 2001