Optical storage has been around for a quarter of a century and has its loyal users, but it seems to have landed in a small, niche market. However, with the introduction of professional blue-laser high capacity optical storage (HCO), that may be starting to change because companies are now being offered better pricing and more capabilities. So is optical on its way to the storage mainstream?
According to the Optical Storage Technology Association (OSTA), the ongoing development of optical technology has opened up new possibilities. Migration software now allows unused data to be moved from its initial location to an optical device, where it resides until it is needed. Since the only thing that touches the media is the laser, proponents of this storage method say it is the most durable way to store and archive data. The folks at OSTA say optical storage is no longer a niche market, since optical storage solutions are also used in a wide variety of applications such as document imaging, records retention, backup systems, desktop publishing and CAD/CAM.
Some analysts and industry experts believe that companies with requirements for write once, read many (WORM) storage and who need long term (10 to 15 year) storage without migrating data should consider HCO as an alternative to disk or tape archival storage.
"HCO promises much longer shelf life, although companies will have to migrate what they have to HCO once and then just maintain drive systems to read them," said Ed Walker, vice president of Call/Recall, which develops high-performance, terabyte-class optical storage systems.
Jonathan Buckley, vice president of marketing at PowerFile, which specializes in archiving appliances for permanent storage of digital content and assets, said there is a rapidly emerging need for an "archival tier of storage" within large storage enterprises, which consists of data assets which have a minimum useful life of 15 or more years.
"Over these time periods, magnetic-based storage systems, which are designed for speed rather than longevity, demand relatively high maintenance, which translates into cost and risk," said Buckley. "It is the avoidance of cost and risk over the archival period which makes the new optical-based storage systems so appealing."
So should companies that have capacity requirements of up to 60GB in a single drive (38TB in a single optical library) and media retention requirements of up to 15 years without migration consider HCO as an alternative to disk or tape?
Although some industry experts say the answer is yes, Buckley said customer storage volume size requirement is irrelevant in driving new optical considerations because longevity and permanence of data are the most important attributes.
The reason for this, he said, is that properly devised enterprise storage systems transcend the physical limitation of "the platter" by pooling (or virtualizing) the underlying optical disc or magnetic disk drives.
"I do not believe that there is a disk, tape or optical company in the market today that can't provide a single volume of at least 60GB or a set of volumes totaling 38TB," said Buckley.
"The exception to this consideration of volume size is if the customer is looking to burn disc and remove the data offline," he said. "In this case, it is important for the full data set to be on a particular disc."
However, he said this is not an enterprise solution but rather a small business solution. "I have found that enterprises simply do not have the personal time or the propensity for risk involved with burning and replenishing media," he said.
Walker said HCO promises a much longer shelf life. "In fact, our optical storage media has been in our lab now and at government sites for about 15 years with no degradation," he said.
Another issue facing optical storage is the fact that many vendors have discontinued CD/DVD libraries because of reliability issues with consumer-grade commodity drives, and companies considering HCO want to know if it is any better.
"Perhaps, but only time will tell," said Walker. "I believe that the HCO systems should have stricter tolerances to ensure more continuous smooth operation."
CD/DVD libraries, without the advantage of any system-level error-correction, have been proven to be too unreliable for the enterprise, said Buckley. "The very same is true for Serial ATA (SATA) drives, which we now know can be made enterprise-ready through the employment of system-level software techniques upon which companies such as Network Appliance are built."
Buckley believes that past experience with CD and DVD storage in the enterprise market has led to the continued relative decline of optical storage. "It makes it that much harder to have companies now take a second look, but they are starting to do so due to the growing pain of archive," he said.
Meeting Regulatory Requirements
As versatile as optical storage is, another issue facing companies is whether or not optical storage is appropriate for organizations that have significant long-term regulatory requirements.
Walker said optical's shelf life, growing capacity and low costs make it a great solution for archiving.
But Buckley said that for companies looking to store regulatory liabilities that is, data that they are required to keep for a period of time putting that data on a permanent storage platform could pose a problem because the data cannot be readily deleted at the end of the compliance period. "Compliance-driven data tends to be relatively small in total bulk, and therefore the cost advantages of HCO may actually be eroded by the added risk that the company endures by maintaining it past its required time," he said.
In a small and mid-size business survey last year, Gartner found that 34 percent of worldwide respondents indicated that they are using optical storage for on-site archiving, and another 19 percent were considering using it. Granted, the survey was focused on the SMB market, and it did not differentiate between various optical storage technologies (CD, DVD or professional HCO), but it did indicate that there is a user base that finds high-capacity optical storage very attractive.
Many industry experts believe that optical storage, when compared with other random access removable media storage solutions, is a growing alternative because it has the highest capacity available, the lowest cost per megabyte, the longest archive life of any media, the widest environmental condition tolerance, and the only technology that scales from laptops to enterprise solutions.
Still, the technology has a number of obstacles to overcome, and the biggest just might be its reputation as a consumer-oriented technology not suited for enterprises. But a new generation of optical technologies aims to change that perception.