Talk about opening up a can of worms. As recently as perhaps five years ago, corporate users had limited options when it came to write once, read many (WORM) storage offerings, but now they have a virtual bait and tackle kit full of products available to them, whether tape, optical, or disk-based products.
Peter Gerr, an independent storage analyst, explains that WORM-enabled magnetic tape was introduced by Storage Technology Corp. (StorageTek) in the form of VolSafe media back in 2000.
Today, Plasmon Inc. owns the market with both traditional CD and DVD WORM products Gerr says. In 2003, Plasmon introduced ultra dense optical (UDO), the first optical storage offering to use blue laser versus red laser technology, which had been used up until that time -- and still is used -- in legacy optical storage.
A plethora of other offerings is also available today. Hewlett-Packard Co. (HP) tape products supporting WORM include the HP StorageWorks ultrium 960 tape drive and the HP StorageWorks SDLT 600 tape drive, both of which offer up to a 30 year shelf life with backward read compatibility. In addition, Maxell Corp. of America is now shipping its Linear Tape-Open (LTO) Ultrium 3 tape media. LTO is an open and adaptable tape format created by Certance (now owned by Quantum Corp.), HP, and IBM.
Implementing WORM productsJim Wheeler, director of market development for Pegasus Disk Technologies, Inc., San Ramon, Calif., advises users to deploy a tiered storage approach to regulated data. He notes that short-term data -- anything stored for under three years -- would be good to have in a hard drive WORM solution such as EMC's Centera or Network Appliance Inc.'s SnapLock product. He adds, however, that these solutions are "always online and do not scale without significant hardware upgrade costs."
For longer term data, anything over three years, Wheeler says that optical WORM products are best because their shelf life is typically between 30 to 50 years. These solutions also offer stability and portability. According to Wheeler, both optical and hard drive WORM solutions are well suited for single-file retrieval, and data indexing and searching.
Finally, tape solutions will also work well in this archive tier, according to Wheeler. However, users must be aware that the shelf life is not as long as optical. Since the data density is far greater, the costs are lower. "The downside is the complexity of searching and indexing tape solutions," he says.
According to Gerr, WORM tape is now offered by most major tape storage vendors, including HP, IBM, Quantum, StorageTek, SpectraLogic Corp. and other companies. It is offered in a variety of formats, including digital linear tape, super digital linear tape, LTO and advanced intelligent tape.Disk-based WORM products Gerr explains that there are two generations of WORM media, "the first being dominated by optical, and to a lesser degree WORM tape, which were the only choices for immutable data retention until 2002 when EMC released Centera, which was the first mainstream, commercially available product to include disk-based WORM."
Network Appliance Inc. followed EMC's Centera, Gerr says, with its SnapLock product, which he points out takes a different approach to WORM than Centera, but delivers more or less the same functionality. Similar offerings in the same category include IBM's DR550, HP's Reference Information Storage Service, Permabit Inc.'s Permeon and Archivas Inc.'s ARC. Gerr notes that StorageTek has also recently announced a disk-based WORM product called IntelliStore and Sun Microsystems Inc. (which recently announced plans to acquire StorageTek) has a similar product in the works, code-named Honeycomb. Currently, Sun sells a combination of WORM-enabling software in conjunction with a NAS system for compliance-oriented environments.
Keep your SOX onSince myriad WORM offerings currently grace the marketplace, storage administrators must consider not only capacity and other technical product features, but always keep in mind their corporate compliance concerns. These concerns include whether or not any given solution will help an organization adhere to the Sarbanes-Oxley Act ( SOX) and other regulations concerning the retention and storage of data.
Dianne McAdam, senior analyst and partner with the Data Mobility Group in Newton, Mass., observes that "WORM is commonly used to ensure that data that is regulated cannot be modified -- so it is used to ensure that e-mails that are regulated by SOX, for example, cannot be modified for the duration of their retention period." She adds, "hardware WORM is vendor proprietary, software WORM, such as [that offered by] Permabit, does not lock one into any disk-based system. There is also a cost associated with specialized WORM systems, such as Centera. WORM tape is much less expensive than WORM disk, but tape does not have the fast random access that WORM disk can support."
With the explosion of WORM offerings currently on the market, Wheeler says that the onus is now more than ever squarely on the shoulders of storage administrators to determine exactly what sort of media works best for them and how compliance will best be accomplished for their organizations. "While SOX defines clear rules for storing corporate records, it does not specify the exact manner in which records are to be stored. SOX also does not certify any kind of storage type," Wheeler says. "The burden is put upon the user to make sure that they meet the sections of the regulation at the time of the audit."