Often mentioned in the same breath, backup and archiving are actually quite different processes, involving different capabilities and often with competing requirements.
According to Graham Irving, managing director, K-PAR Archiving Software, backing up data creates an exact mirrored copy of a company's information. It creates a "reserve" resource, should something happen to the original data.
Archiving applies to data that is likely to be needed again. "Archiving is essentially an intelligent form of backup - logically placing information where it can easily be found and retrieved for future use," he said.
According to Jon Murray, regional program manager, EMC South Asia, each concept plays an important role in information life cycle management, and each has different and distinct characteristics and applications.
"Most of the information that companies back up every day or every week really hasn't changed so companies are backing up things that aren't necessary because they don't change over time," he added. "The way to do backup is to first look at data that really doesn't change anymore and archive that. This means you back up less and your recovery process is faster."
Backup jobs are pre-scheduled and initiated by the software application. "Ideally, the backups are automated and can be scheduled for off hours and run unattended. Any abnormal results of the backup job are reported clearly and concisely by the software application," said Kelly Beavers, vice president, Investor Relations & Business Development, Exabyte. "The software application provides a clear and intuitive user interface, especially for managing the restoration of data. All data should be restored without user intervention -- with no read errors, no swapping tapes between drives, no cleaning of drives."
From Exabyte's perspective, "the natural evolution of backup and restore leads directly to tape automation", said Beavers.
Tape is also positioned as an inexpensive archive medium. "When you archive a project, you put everything on the tape -- the data you produced in your designs, analysis, calculations and all of the software applications (even the operating system for some projects) you used to produce your results. If you need to retrieve the data at some later date, you may have problems with compatibility because upgrades and other changes to your application software are not perfectly compatible with your old data," said Beavers. "The value of tape in this scenario is that it can hold all your business data -- user files and applications -- to ensure compatibility during a restore because it also holds the legacy application data, an aspect that is invaluable after several upgrades or new software rollouts months or years into the future."
Increasingly, disk is also entering the equation.
From EMC's perspective, for example, backup is typically best achieved with solutions that include EMC Clariion with ATA disks (EMC Clariion Disk Library) and/or tape, depending on the service level and functional requirements, said Murray.
Archiving, on the other hand, is typically best achieved with solutions that include a WORM-based content addressable storage device such as EMC Centerra, he said.
WORM or Write Once, Read Many functionality serves the regulatory compliance market by allowing information to be written a single time and prevents the data from being erased.