New data storage options for the future

By Taro Ikushima, Senior Product Manager, TDK

With the trend towards a greater use of IT systems and electrical databases in companies continuing, data back-up is becoming increasingly important. At the same time,
new legislation now requires firms and organisations to manage company databases safely and according to defined rules. In such a fast changing business environment, efficient data management has not only become an essential part of business compliance, it occupies a central role in the creation of any successful and sustainable business.

There are several types of data recording media available today. While the RAID (Redundant Array of Independent Disk) system grows in popularity as a data back-up medium, removable storage media such as LTO and Blu-ray (BD) has a pivotal role to play in the storage agenda providing essential advantages such as cost, mobility, longevity and reliability.

Built on the long legacy of data tape, LTO Ultrium for example is a feat of tape technology, achieving high reliability and durability. The latest LTO Ultrium 3 tape can hold data up to a massive 400Giga Bytes (800Giga Byte with compression). Having 704 tracks in 12.65mm wide tape, data density reaches incomparable levels.

With an archival life of 30 years in closed room conditions, LTO Ultrium meets most users’ data storage requirements. Aside from capacity, the longevity of LTO Ultrium has other benefits. The mechanical stability of LTO tape is sufficient for at least 20,000 tape loads and unloads, which relates to approximately 50 years of daily use. The future continuity of the LTO format is also clear making it a secure choice for organisations needing to back-up or archive large amounts of important data. IBM, HP and Quantum and several tape manufacturers all support LTO and migration from the current Ultrium 3 to a sixth generation product is already mapped out in two-year increments.

Blu-ray Disc (BD) is the latest optical disc technology and is seen by many as the next generation DVD. While considered to be a consumer medium for recording High Definition video data, some key characteristics of BD indicate that it has the capability to offer a viable solution in the business environment.

Among the principal benefits of optical discs are random accessibility and durability, meaning that they can be used to keep important data in a safe environment for long periods of time while still allowing accessibility at frequent intervals. Despite these adaptable qualities, the installed base for this medium has traditionally been restricted for two main reasons – one being its small capacity and the other its lifetime.

Now with five times greater capacity than DVD, BD has overcome the first of these issues. Utilising the advanced blue-violet laser beam, it achieves 25GByte and 50GByte (dual layer) data capacity on a 12cm diameter disc. The larger capacity per disc means higher efficiency of shelf space usage. By comparison, the single unit of a BD optical library system can store over 30 Tera Bytes of data while DVD can hold only 6 Tera Bytes. The cost per Giga byte is also significantly reduced.

The longevity of the optical disc for CD and DVD recordables presents a challenge. The chemical dye in the recording layer which is transformed by the heat of laser beam, changes its reflectivity when data is recorded and thus deteriorates over time. Adding to the problem, poor formulation of the dye in low quality media accelerates this process. Although “A brand” media in the market has comparable archival life with major tape media such as LTO Ultrium, it has not until now been long enough to differentiate optical disc from tape.

BD has again overcome this weakness. BD recordable (BD-R) media now employs metal alloy of Cu (Copper) and Si (Silicon) in its recording material as shown in Fig. 3. The metal alloy is far more stable than chemical dye, lasting much longer than previous recordable media. With lab tests, TDK, a board member of Blu-ray Disc Association, has confirmed that the archival life for BD-R is now more than 100 years in a closed room environment. A special hard coating on the disc surface developed by TDK called DURABIS further enhances the disc’s durability.

Like LTO then, BD also has a roadmap for the future. With high capacity and longevity, BD can eliminate the disadvantages of previous optical disc technologies and has the potential to become an ideal business digital archive solution.

In the climate of growing and diversifying demand for data storage, media formats are evolving with businesses and are helping to ensure future business continuity. Many of the old technologies remain valid, but the LTO and BD formats have come of age and should now be recognised as two of the most promising and dependable options for removable data storage.