Hot tape may get a cold reception |
 |
By Alan Earls
05 May 2008 | SearchDataBackup.com |
|
|
Earlier this year, Imation Corp. demonstrated a new technology that at least doubles the data storage capacity of existing LTO-4 tape. At the Information Storage Industry Consortium (INSIC) Tape Program Quarterly Technical Review in San Jose, Calif., Imation scientist Denis Langlois presented results of the company's technology development program that could enable as many as 10,000 tracks per inch on conventional magnetic particulate LTO-4 tapes, made using conventional, low-cost substrates (base films). The new Imation technology utilizes a combination of an amplitude-based "servo" pattern that puts the adjacent tracks on the tape, a unique thin-film head technology for recording and an innovative multilayer magnetoresistive array for playback.
But, despite this impressive achievement, analysts question whether the development will have much of an impact on larger trends in the tape market. Robert Amatruda, a research director in IDC's storage program, said, "This demonstrates that there is still innovation to be done on tape and underscores the fact that it remains a cost-effective means of storing data." Still, he admitted, innovation won't necessarily translate into adoption by the LTO organization, and that could be a problem.
|
|
|
|
|
This demonstrates that there is still innovation to be done on tape and underscores the fact that it remains a cost-effective means of storing data.
Robert Amatruda,
research director, IDC's storage program
|
|
|
|
|
|
|
|
|
|
Ramnath Subramaniam, Imation's R&D director, said what his company showcased is a breakthrough, which overcomes fundamental system-related issues of dimensional stability in tape. First, he noted, tape has been bedeviled by tracking errors. Second, vendors haven't been able to maintain tight enough tolerances in the construction of read/write heads. Third, Subramanian pointed out the inherent difficulties associated with dimensional changes that occur in the polymer substrate of tape. "The result is that when you write on tape, you must leave room for possible errors between writing one track and another and that ends up limiting density," he explained.
Subramanian said his team has come up with a way to write multiple tracks simultaneously, which makes it possible to write a far greater number of tracks accurately compared to what would occur if tracks were written individually. "We have paired that with proprietary servo patents that let us track more precisely, with a standard deviation of only 40 nanometers compared to the upcoming LTO-5 standard deviation of 120 nanometers," said Subramanian. Finally, Imation researchers have created a sandwiched read head, which permits reading of all the tracks simultaneously by means of two layers of readers staggered close to each other. The result is that using LTO-4 media, Imation has already demonstrated the ability to write 1.6 TB on media that would normally hold 800 GB. That was with 5,600 tracks per inch, "but we think we could probably do 10,000 tracks per inch," he added.
And what of compatibility? Langois admitted there's some disconnect there, because existing LTO-4 uses a serpentine writing scheme. Still, he pointed out, with a sandwich-type read head, there's no reason why backward read compatibility couldn't be included in a system utilizing the new density.
The bottom line, said Subramanian, is that there's nothing to preclude commercialization -- except the fact that Imation isn't in the business of manufacturing read-write heads. "So, we are looking to OEMs to see the value of this and move toward commercialization," he added.
However, Bob Passmore, research vice president at Gartner Inc., said despite the great progress Imation has demonstrated, "it won't change the overall vectors in the market -- tape has always been about backup, but now it is increasingly becoming the medium for archiving."
"In the short term, the use of disk arrays as virtual tape systems hasn't eliminated tape, but it has reduced its role and the frequency of its use from primary recovery medium to a secondary recovery medium," he added.
Thus, said Passmore, doubling the capacity of LTO-4, or any other tape, while it might make a marginal difference in purchasing decisions, still won't change the big picture very much. "This isn't going to be a tilting point for most decision processes," he adds.
However, Subramaniam stressed the new Imation technology isn't specific to any one standard. "At some point, all the standards will come up against the same limits imposed by dimensional stability issues in tape -- and we believe we have the answers," he said. "We achieved success right off the bat and we believe with refinements we can improve even further."
About this author: Alan R. Earls is a Boston-area freelance writer focused on business and technology, particularly data storage.
|
|
|
|
