I think it depends a great deal on the quality of the tape drive, the tapes used, and how often you intend to back up.
CD-Rs are not idiot proof. It's been my experience that they are not quite as resiliant as professionally pressed CD-ROMs. If they get scratched, you stand a better chance of data corruption. This may depend on the disc though. Cyanine discs (used for both CD-R and DVD-R) used a notoriously unstable dye process, and will break down over time. That makes them unsuitable for archival and backup purposes. Chemical stabilizers have been added to the process, but I still wouldn't trust them for anything I wanted to keep long term. Phthalocyanine and Azo CD-Rs are a much better bet, but still not perfect. All CD-Rs are susceptable to oxidation over time, except for certain very high-end gold discs.
All CD-Rs degrade when exposed to UV light, so put them in a dark place (like a folder).
Another problem with using CD-Rs is it's usually not an automated process. You'll have to be there to switch out discs. Where with large magnetic media, such as huge tape drive or external HD, you can automate the process. Even writable DVDs don't have the capacity large enough to back up modern hard drives.
Basically, this means that well-handled and quality CD-Rs might be good for backups you might want to keep for a couple of months, but should in no way be trusted for archival purposes.
Amsuingly, the best backup method for a computer HD is probably another HD. Provided you keep them clear of magnetic sources, avoid shock damage, and limit the read/write cycles, they'll last a really long time.
In 2057, when we're all using holographic memory, this discussion will be academic.
- John
CD-Rs are not idiot proof. It's been my experience that they are not quite as resiliant as professionally pressed CD-ROMs. If they get scratched, you stand a better chance of data corruption. This may depend on the disc though. Cyanine discs (used for both CD-R and DVD-R) used a notoriously unstable dye process, and will break down over time. That makes them unsuitable for archival and backup purposes. Chemical stabilizers have been added to the process, but I still wouldn't trust them for anything I wanted to keep long term. Phthalocyanine and Azo CD-Rs are a much better bet, but still not perfect. All CD-Rs are susceptable to oxidation over time, except for certain very high-end gold discs.
All CD-Rs degrade when exposed to UV light, so put them in a dark place (like a folder).
Another problem with using CD-Rs is it's usually not an automated process. You'll have to be there to switch out discs. Where with large magnetic media, such as huge tape drive or external HD, you can automate the process. Even writable DVDs don't have the capacity large enough to back up modern hard drives.
Basically, this means that well-handled and quality CD-Rs might be good for backups you might want to keep for a couple of months, but should in no way be trusted for archival purposes.
Amsuingly, the best backup method for a computer HD is probably another HD. Provided you keep them clear of magnetic sources, avoid shock damage, and limit the read/write cycles, they'll last a really long time.
In 2057, when we're all using holographic memory, this discussion will be academic.
- John