With the proliferation of computer based DAW’s the question of archiving data is at the forefront of many people’s minds. And there is a lot of confusion about the topic. Today’s question is representative of many we get.
“Other than speed and capacity, are there any disadvantages to using a CDR or CD-RW for Backup/Archiving? I seem to remember from an earlier issue of inSync that there may be some questions about the quality of the back-up made with a CD-R. In other words, the image burned to disk might not be a mirror of what was on the hard drive. Could you please clarify?”
In short, CDR and RW are excellent ways to archive material on a hard drive. The media is VERY inexpensive and is pretty reliable. These days speed isn’t even much of a problem. A good burner can burn a 650 MB disc in about 8 minutes. Concerns over CDR reliability do not really come from a question about being able to write the data correctly in the first place. This has never really been a problem (unless you are talking about burning audio discs). Most of the popular software programs for burning CD’s have routines they can run to check the disc after burning. This basically just compares the data on the newly burned disc to the data on the hard drive. If it passes this test it is a good disc. The concern arises in regard to the longevity of the discs. There are ongoing studies about this. Obviously it’s difficult to accurately predict how long the various types and brands of discs will last because they’ve only been around a few years, but the general consensus is that the media is going to be good for some number of years. Maybe that’s 5 years, and maybe that’s 55 years. No one really knows for sure and it’s going to vary quite a bit. There have certainly been isolated occurrences of discs failing after only a few days. Your best bet, if the data is really critical, is to make two or three discs and store them in different locations. They don’t cost much so this shouldn’t be a hardship. For professional installations we still recommend professional solutions such as DLT and AIT. Their only disadvantage is cost, but in every other way they are at least as good, if not substantially better than CDR.