How is the role of magnetic tape changing today?
To understand how the role of tape is changing today it is important to understand the life cycle of data in a typical organization. Active changeable data is what we typically think of as online data that may be written -- as well as read. A relatively high probability of access and the need for low latency response time characterize this data. Active archive data is fixed content that still has to be available online, but has lower frequency of access and can tolerate longer response time latencies. A deep archive is production data that has to be housed for legal or historical reasons, but may very well never see the light of day and can tolerate recovery latencies that may measure in days.
Why does this matter? Well, active changeable is the pool of data that we interface with most frequently. In addition, the role that magnetic tape once had in providing the first data protection copy is rapidly being replaced by disk-to-disk backup approaches for a number of reasons, including recovery time. Does this mean that tape has no role in protecting active changeable data? No. At least three lines of defense (which means three distinct copies) have to be made and tape may very well play a role at least in the last line of defense (as it provides I/O isolation to prevent data corruption from a virus, among other things).
However, organizations are coming to the realization that the vast majority of their data is fixed content data -- meaning it’s suitable for archiving. Tape is likely to have a major role in both active and deep archiving. The seemingly never-ending growth of data (including the newly popular “big data“) refers to mostly fixed content data, and tape scales much more cost efficiently than disk to meet this need. Whether it’s in-house (private cloud) or tape in the cloud (public cloud), magnetic tape needs to receive the proper attention.
This was first published in May 2012