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UDO upstages MO
Until recently, the primary optical storage offering for this market was MO disk. MO uses a 5.25-inch disk read by a red laser. Current MO storage capacity is 9.1GB per disk. The disks can be loaded into multidrive jukeboxes that scale to multiple terabytes. "The problem with MO is that it's running out of steam," says Tom Sas, product manager for Hewlett-Packard (HP) Co.'s automated storage group in Loveland, CO. HP offers an MO-based system, but MO has reached its maximum capacity because of the size of the dot a red laser can manage. "We can't pack any more density on the disk, so MO will top out at 9.1GB," says Sas.
Picking up from there is the blue laser, which is the basis of several optical disk technologies. From an enterprise storage standpoint, the most promising is the UDO format. UDO uses a 5.25-inch double-sided disk that packs 15GB per side, or 30GB total. The roadmap for UDO currently stretches out to 60GB capacity, and then to 120GB capacity by 2007 or 2008. Because the disk form factor remains consistent from MO to UDO, organizations will be able to convert their existing MO robotics (jukeboxes) to handle UDO, although there will be no read/write compatibility. DVD is another optical 5.25-inch format that's non-proprietary.
MO disk technology will likely be around for another 10 years or more, but vendors have basically stopped trying to enhance it. "For some customers, MO is all they need.
UDO is no sooner ramping up than a potentially disruptive optical storage technology--holographic optical--has appeared. Holographic optical is being developed by InPhase Technologies, Longmont, CO. It uses roughly the same size disk as MO, but promises to put 300GB on each disk. Its roadmap calls for 800GB and then 1.6TB within a few years, says Liz Murphy, InPhase's vice president of marketing. Holographic drives will look like SCSI devices and provide random access like any disk technology. But Murphy doesn't expect the first commercial products to ship until the fourth quarter of 2006. Early adopters are expected to be media and entertainment companies that need high storage capacity for movies and high-definition TV.
At one point, optical storage was envisioned as the midtier of a hierarchical storage management strategy. It never panned out. "Optical would have required a usage change. The whole architecture was tuned to tape," says IDC's Schlichting. Instead, optical was adopted primarily for its WORM capabilities.
Information lifecycle management may yet revive interest in optical storage. "Certainly, optical is more viable now as EMC, Computer Associates, Veritas Software and others offer support for optical," Schlichting continues. IBM Corp., on the other hand, hasn't been active in optical storage for several years.
Optical storage shows up most often in the medical, financial and government sectors (see "Where optical works best," this page). It's also used in the media industry for the storage of digital content, according to IDC. The Dallas Morning News, for example, recently replaced a small DVD jukebox with a Plasmon UDO jukebox to permanently store photos shot by its photographers.
"We have the entire shoot if a question ever arises. We also go back and reuse our shots regularly," says Bob Mason, director of publishing systems at The Dallas Morning News. Now that it has the technology, the company is looking to expand its use of optical into areas like regulatory compliance and financial records.
Mason said that before purchasing the UDO jukebox, "we looked at tape because of its low TCO [total cost of ownership], but ruled it out due to its lack of permanence." UDO gave the newspaper what it wanted: WORM permanence, high reliability, a 50-year lifespan and a fast response to user searches. The newspaper looked at disk systems, but rejected them. "We had concerns about the amount of floor space required. Also, disk systems aren't perfect. You have to back them up. In the end, the total cost of ownership was too high," says Mason. The total cost of the UDO optical storage system came to approximately $150,000. This includes 638 disks, two jukeboxes for replication to a second data center, replication software and digital asset management software from The Software Construction Company, Alpharetta, GA.
DigiLink Inc., an Alexandria, VA, pre-press company, takes content provided by its customers and creates the type of electronic files needed for printing. In recent years, the firm has offered the actual printing as well. DigiLink takes customer content and initially stores it on a SAN. After the job has been completed, it sends the files to a 700-disk DVD jukebox for long-term archiving.
Before going optical, the company archived customer files on DLT tapes. "After four years of growth, we had over 100 DLT tapes," says Dave Whetzel, DigiLink's manager of technical operations. DigiLink also found it difficult to pull files from the tapes. With optical storage and Media Beacon digital asset management software, DigiLink and its customers can pull any file from the jukebox using a Web browser.
The firm opted for DVD over UDO, although UDO offers more capacity. "We didn't want something proprietary. DVD is a nice, open technology," Whetzel says. "I could [even] pull a disk and access it in a Mac," but he doesn't expect to.
Currently, each DVD holds 4.3GB of data. After one year of use, the company has filled 450 sides of DVD storage. The optical storage is accessed from the DigiLink's Windows servers through a StorageQuest Inc. appliance that acts as a NAS head for optical storage. The 700-disk jukebox can accommodate 1,400 sides. By the time DigiLink approaches capacity, "we expect DVD capacity to increase through the use of double layers," Whetzel says. Another option at that point is to plug in a second jukebox.
"It's just a SCSI connection out of the StorageQuest NAS head. We can daisy-chain more jukeboxes," he says.
This was first published in June 2005