{mosimage}Two-years ago, several small disk storage start ups hungry for their first sales and a few large enterprises, who were losing ground to tape, proclaimed that tape won’t be needed as “their” new disk products were replacing tape. Today, those critics aren’t so bold with their statements having come to realize that their disk-based products are perfect complements to tape subsystems.
By Rich Harada
At first glance, tape storage seems to be something from a past era, a medium that couldn’t possibly still keep pace with today’s enterprise storage needs. It is true that tape is from a past era while it’s also a technology whose major developers including Fujifilm, Maxell, Quantum, Sony, and StorageTek invest over a billion dollars each year. Tape storage products have been sold for more than 50 years and continue to be in high demand. Despite the many attempts to displace tape with other storage technologies, it appears that tape is here to stay.
“There’s just no other data storage solution that has been available or is expected to be available that is removable, transportable, and has a lower cost per GB than tape,” says Chris Smith, Sony’s general manager of Data Media Business Development. “Tape’s use in backup, as well as archive and disaster recovery applications, is highly attractive because of these benefits and also due to the reliability and longevity of the media.”
IT professionals realize that fellow employees within their companies are finding it increasingly more difficult to keep just the important files. As more and more data is being sent to the data center for future use, the challenge of where to store this data is of even greater concern. If the file is active, whereby its use and revision is expected, multiple versions of that same file would add an exponential amount of storage capacity.
{mospagebreak}“Adding capacity with tape is significantly easier than installing new hardware, most often, a tape library would just need more tape cartridges,” says Bob Raymond, engineering manager at StorageTek. “Tape’s ability to store data within an automated tape library and take advantage of the remove-ability for archiving and to move between data centers makes it ideal to handle a greater amount of data than was initially planned.”
With the assurance that data will be available and restored if the network system’s integrity is compromised, the back up from the tape subsystem would keep the data center operating. Although a data center’s need for recovery may be seldom, if at all, its data could be retrieved from an off-site warehouse when the company is audited or a request is made to provide information to look at historical trends or even to settle a legal dispute.
If one reviews the technical specification and schematic diagrams of the basic tape drive and media technology, he’ll find that tape uses the best of the magnetic storage technologies. In fact, tape’s technology is a refinement of some of the same technology used in hard disks. The notion that magnetic disk capacity would outpace tape is also misleading. As improvements in magnetic media design continue, the developers of tape drives and media have more technology to work with to improve their products. But even if and when magnetic media designers, particularly disk engineers, do hit the areal density wall, tape engineers will still have many generations of capacity improvements to come, due to the 800:1 ratio in areal density that currently exists between disk and tape design.
Another way to look at this would be to say that current tape cartridges contain 800 times the recording surface of a disk drive. Tape has seventy-five times more density than a comparable hard disk, so tape has a long way to go before capacity is at its limit. With disk reaching its theoretical limits, tape continues to increase two and three fold in capacity.
“It’s better to say that disk complements tape, and together with application software and automation provide an excellent data storage system,” says Steven Pofcher, Maxell’s senior marketing manager. “Many companies are now marketing the two technologies together for example designing virtual tape libraries to work with ILM applications.”
{mospagebreak}A virtual tape library (VTL), sometimes referred to as virtual tape server (VTS), offers storage to a disk cache, which acts as a fast writing buffer. When the data is not required to be in primary storage, it is sent to either disk cache or a tape drive within a tape library. ILM is a policy-based software model, which directs the system to always prioritize and store individual pieces of information on the most cost-effective storage resource available.
Tape may not be viewed as the flashy trendsetter, but it is viewed as ‘old reliable’. Storage technology, in general, advances and improves while decreasing in price over time. Disk technology is three to ten times more expensive than its cousin tape. While a 160GB disk drive might sell at U.S.$120 or $0.75 per GB, a tape cartridge with the native 160GB capacity sells for $40 or $0.25 per GB and using 2:1 compression is $0.125 per GB.
“The increase in capacity of a tape cartridge to 1TB of uncompressed data will be realized in the next few years,” says John Goode, Quantum’s marketing manager. “Speed improvements are outpacing most networks while capacity gains using compression are outstanding for even the largest data center.”
Based on a new engineering research report by Information Storage Industry Consortium (INSIC), the technology to produce a single tape cartridge should be available to create 16TB of uncompressed storage with data transfer rates of 832MB per second by 2015. The research and development teams of major data storage manufacturers joined together to share their recommendations on how to maximize capacity and throughput while retaining today’s 5.25-inch drive standard. Although this group of elite engineers provides input on the future specifications of tape, the actual product that is shipped will be market-driven and depends on each manufacturer.
Drive, media, and software vendors are creating new ways for tape to work with disk-based products. Some are offering bundled hardware configurations with disk to handle compliance used to store regulated data. Others are automating the configurations with sophisticated libraries and application software for specific applications such as regulatory compliance.
{mospagebreak}“WORM tape was developed to accommodate the need for data permanence required to meet compliance mandates,” says Rich Gadomski, vice president of Fujifilm. “With high capacity and the ability to ensure that no modification can be made, WORM tape can be used to comply with regulations including HIPAA, Sarbanes-Oxley, and SEC 17 a-4.”
Companies use tape for multiple reasons. Most just rely on tape to store fixed and variable content. With new applications including regulatory compliance and video streaming, tape continues to be engineered to handle the massive amount of data that needs to be stored. Tape has been used to be the final destination for such data. Without tape, companies are at risk of losing their precious assets. Tape technology is here to stay. Tape, in fact, might outlive all of us as it continues to be the most effective storage medium and also, the most adaptive storage technology for over 50 years.
Long live tape!
Rich Harada is president of the Tape Technology Council, the primary industry resource for tape storage technology, which acts as a conduit for information exchange between manufacturers and the industry.
