CD, DVD storage won’t stem the overwhelming flow of documents, data and information you gather and receive every day, but it does have the higher capacity we need. It also provides portability, random access, longevity (50+ years), and data reliability … all at a storage cost of less than $.01/MB.

Choose Media As Though Your Data Life Depends On It

G.A. “Andy” Marken

Choose Media As Though
Your Data Life Depends On It
By  G.A. "Andy" Marken

CD, DVD storage won't stem the overwhelming flow of documents, data and information you gather and receive every day, but it does have the higher capacity we need. It also provides portability, random access, longevity (50+ years), and data reliability all at a storage cost of less than $.01/MB.

If you get the feeling that you are drowning in information and it's all too valuable to simply throw away, you're probably righton both counts.

According to Richard Saul Wurman, author of Information Anxiety, the daily edition of the New York Times contains more information than your grandfather encountered in a 10-year period. To make matters worse, Wurman notes that our information supply doubles every five years. With the convergence of voice, video and data, combined with the global reach of the Internet and the Web, there is no end in sight to the volume of information you can obtain and use in your personal and business life.

Information is becoming so valuable that you can no longer simply read it and discard it. In fact, Jack Welch, former chairman of General Electric, noted that an individual's ability to learn and translate that learning into action rapidly is a person's ultimate competitive advantage. As a result, you and I store more and more information on our computer for fast, easy access.

It's no wonder that computer storage requirements grow more than 50% a year, and even today's hard drives with 80 Gigabytes are quickly filled. If logic prevailed, you would go through your files and discard the old documents, images, presentations, video clips and data when your hard drive was close to being filled. But we all know that the day after the information is discarded, you will need the data and the time to reconstruct it will require hours or even days which can be costly.

Rather than buy a larger hard drive, there is a better, long-term solution that is economical, easy to install and easy to use. It also provides virtually unlimited capacity. It's the addition of a DVD burner that writes to both CD-R (write-once) and CD-RW (rewriteable) as well as DVD+/-R, RW and double layer discs. The drives are very inexpensive today and software is readily available that will not only write your files to the media but will keep an inventory on-line of the data's location. Depending upon the media you purchase, 650MB and 700MB CD discs will only cost you less than 10 cents. DVDR media (4.7GB) is 30-50 cents and DL (8.5GB) media is $3-4.

Just a few years ago, even CD media was expensive and there were only a handful of media manufacturers such as Verbatim serving a very small market. But this year, analysts project that more than 900 million CD-R discs and more than 400 million CD-RW discs will be sold. DVD media production will be about 1.3 billion of single layer media and about 500 million double layer discs.

The burgeoning demand for globally standard optical disc based storage has attracted a growing number of suppliers. Today, there are more than 25 manufacturers and private-label producers - some reputable firms and a large number of entrepreneurial organizations that produce low-priced, inferior media with storage quality that can vary from day-to-day, disc-to-disc.

Except for the color and artwork, all of the discs you see when you visit a store look very similar.

If you're lucky, you only know the media is bad after you have stored a number of files or produced your own video or MP3 audio disc and try to play them on the recorder or on another player. If you're unlucky, you find out that the media has gone bad six months later when you attempt to recover the data that is now stored only on the media.

To protect themselves, buyers need to know:

  • Will media from manufacturer X record at the desired speed?
  • Will it perform well at that speed?
  • Will the disc, once recorded, be readable on the wide variety of players available?
  • Will it retain data, over time, under less than ideal conditions?
  • What type of guarantee does the manufacturer provide with its product?
  • Let's begin by putting cost differences in perspective.

Despite the fact that optical disc quality and capabilities can differ widely, disc costs vary by only a few cents and can store a volume of data. For example, a single 700MB CD (-R or -RW) will hold 74 minutes of audio, 45 minutes of MPEG-2 video, 5,400 photos, 50,000 or four 4-drawer filing cabinets of documents. A DVDR 4.7GB disc will hold 400,000+ documents or eight 4-drawer filing cabinets, 4,700 color photos, 210 minutes of MPEG2 video, 14 hours of MP3 music. Double that storage capacity for DVDR DL media.

The time expended in gathering this much information and content can be substantial.

The cost of a disc is really irrelevant. What really matters is the value of the data that will be recorded on it. How important is it? How long must it be kept? What would be the cost, in time and money, to replace it? The fact is, if data is valuable enough to be put on a disc, the real issue is whether the disc can be trusted--not how much it costs.

Dye Makes the Difference

The characteristics of a recordable CD - similar specifications exist for DVD -- were specified in the Orange Book II standard in 1990. The technology involves changing the reflectivity of the organic dye layer shown in Figure A. This is typically either cyanine (cyan blue in color), phthalocyanine (more or less colorless) or azo (deep blue in color).

These dyes are photosensitive organic compounds, similar to those used in photography. A microscopic reflective layer--either a proprietary silvery alloy or 24-carat gold--is coated over the dye. Tests show a silver reflective layer provides improved reflectivity and maximizes read/write performance. The silver/blue discs, which are manufactured with a process patented by Verbatim, combine the benefits of silver reflectivity with the increased data reliability and long archival life offered with metal azo dye.

The metalized azo layer also gives Verbatim CD-R media its unique deep blue appearance, which can be easily distinguished from the green of Cyan and gold of Phthalocyanine dyes.

Measuring Durability

Sunlight and temperature, as well as humidity can be a major factor in the degradation of discs, regardless of dye type. Unless precautions are taken during manufacturing, the more extreme the exposure, the faster the deterioration. Verbatim uses industry standard accelerated aging tests to obtain comparative data and to determine an estimated lifetime. Tests show that the media has a projected data life of at least 100 years.

To extend the data life of the media, the reflective layer must remain intact. Manufacturers put a protective layer over the reflective layer because when it is pierced, the reflectivity of the read/write laser is reduced, and this causes media errors. For added protection, Verbatim developed a dual-protective layer production technique, which is standard for much of the firm's media. Extensive tests have shown that the reflective layer remains intact even when scratching force loads up to 120g are exerted on the media.

By leveraging the experience it had gained in developing its CD-R media and drawing on the extensive R&D capabilities of its parent company, Mitsubishi Chemical, Verbatim also contributed to the advancement of CD-RW technology. The same is true of the work done in the newer DVD media as well as next generation HD DVD and BD media.

With CD-RW discs, the disc starts out with the same polycarbonate base; but the recording layer, which comes next, actually consists of four layers: the lower dielectric layer, the recording layer, the upper dielectric layer, and the reflective layer. The upper and lower dielectric layers draw away heat from the recording layer to keep heat from building up. Instead of organic dye, the recording layer is made up of an alloy consisting of silver, indium, antimony, and tellurium (Ag-In-Sb-Te). These elements make the Phase-Change recording possible. After the recording layer, a layer of lacquer is applied for protection.

Like its CD-R media, Verbatim CD-RW discs have a proprietary scratch-resistant coating to protect against damage due to handling and a proprietary printable surface which is optimized for both ink-jet and thermal printing.

The enhanced reliability that is inherent with Verbatim media is becoming increasingly important as the write and read speeds of drives increase and as people store more than data files on their media.

Speed/Quality Issues

Today, discs can be recorded at a variety of speeds. Depending upon the application and the drive, users can write media at 1x, 2x, 4x speeds and newer, higher-performance media is now available for 6x, 8x, 12x and higher speeds up to 52x for CD media and 16-20X for DVD media.

While optimized for high write speeds, Verbatim also suggests that for certain applications, users record in real time. For example, when producing personal audio or video discs, the lower write speed ensures higher fidelity, higher video quality/intensity. Another application where slower speeds are recommended is when the user has a slow system and many small files to record. In this situation, buffer under-run may occur. By slowing the recording speed, the demand on the system is decreased, and buffer under-run can be avoided.

To meet the higher performance requirements, Verbatim engineers have found that silver is an optimum component for the reflective layer. When combined with a Metal Azo recording layer, the more stable silver layer produces optimum overall performance and accommodates the widest range of laser wavelengths (which read and interpret the stored data).

While present lasers operate at 780nm; DVD lasers produce wavelengths of 650nm. Future products will use the lower wavelength laser beams, including blue and ruby lasers. The narrower the wavelength, the more data can be stored in less space. These lasers will also enhance the read/write storage capability of the media even more.

The silver/azo combination has been shown to provide excellent reflectivity, even with lasers that use wavelengths as low as 350nm.

Drive Compatibility

Drive compatibility is another critical factor. Variations in recorders and readers can cause media compatibility problems. These difficulties can be as subtle as slow read times and as serious as the inability to read at all. Problems can also be caused by differences in the write strategy (the way in which the drive's laser is modulated) from one drive manufacturer to the next. In addition, discs from different manufacturers have variations that can affect the tracking of the reader or writer. To avoid problems, purchasers should select media with the widest possible tested compatibility.

To provide media that meets the broadest range of recording requirements, Verbatim continually works to enhance dye and media manufacturing technologies. To ensure read and write performance with every major drive/player; the company works closely with hardware manufacturers. Typically, their engineering staffs are provided with off-the-production line media so they can test their drives' writing and reading performance in data, audio, video and mixed media applications.

While this testing doesn't ensure success if a consumer writes data to unbranded media provided by offshore firms that use older production equipment and techniques, it does provide the branded drive manufacturer with a quality benchmark. It also provides users with the confidence that the data they write to a high-quality Verbatim disc can be read by almost any computer user in the world because drives are standard in almost every computer sold and used today.

In addition to offering broad exchangeability, write-once and rewritable media are ideal for an almost unlimited number of applications.

CD-R media is excellent if you're distributing 1 to 20 copies of corporate presentations, departmental or office spreadsheets or customer/account databases. Increasingly, organizations are using CD-R media for short-run production, prototyping and testing, as well as pre-mastering of single or multiple files for mass production/replication. Individual discs are ideally suited for storing personal or professional audio files; and for permanent storage of photos, images, mixed media presentations or videos.

CD-RW media, which allows users to directly overwrite the disc up to 1,000 times (5 times a day for 200 days), is a reliable solution for system backup, personal or organizational storage and prototyping/work-in-progress activities such as software, game or multimedia presentation development.

For personal home video applications, including downloading/copying TV shows, DVDR media is preferred because of the extended storage time provided. Increasingly, companies produce their own videos - HR sessions, product demos, presentations - where universal DVD discs are ideal for single and multiple copies.

The compatibility with CD/DVD drives that are standard in nearly every computer system sold dramatically simplifies information exchange for individuals and organizations. Data written on high-quality media can be read on nearly all of the nearly 1.5 billion drives, car DVD players and personal audio/video players that are already in use throughout the world today.

CD, DVD storage won't stem the overwhelming flow of documents, data and information you gather and receive every day, but it does have the higher capacity we need. It also provides portability, random access, longevity (50+ years), and data reliability all at a storage cost of less than $.01/MB.

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