WORM (write-once-read-many) tape has been around for years but is wriggling its way into the mainstream, thanks to new regulations governing data retention.
WORM allows information to be written to disk
Quantum Corp. was the latest vendor to announce WORM support for its Super DLT tapes this week. Both StorageTek Corp. and IBM offer WORM tape products: StorageTek with its VolSafe option for its 9840 and 9940 tape drives; and IBM with its 3592 WORM media. Sony Corp. has offered WORM for its AIT-3 and S-AIT tapes for several years.
The revival is having a positive effect on the tape market in general, which analysts say still has legs despite the hype around disk-to-disk backup.
Anyone who tells you that disk will eventually replace tape is underestimating the qualities of tape, according to a report out this week by the Data Mobility Group Inc. It points out four key advantages that tape has over disk when it comes to backup.
First, tape is removable, the report states. Once data is saved to a tape, it can be removed from the system to prevent corruption.
Second, tape is transportable. It can be taken off site without falling victim to shock and vibrations that would damage a disk.
Third, tape has been constantly improved since it was first introduced some time in the Stone Age, meaning that it is highly reliable. Because of these improvements, tapes can sit around for 30 years or more without being corrupted.
And fourth, tape is still the most cost-effective media and not just on a $/GB basis, according to the report. Tape requires one-tenth the power consumption of low-duty disk systems: it takes up less floor space and has infinite capacity; you don't need to add more drives -- simply more cartridges.
The report goes into some depth on the merits of tape emulation and when to choose disk for backup, but presents a convincing argument for why tape will be around for many years to come.