Re: Disadvantages, Full Tape Encryption? WTF?
You say...
"With the LTO consortium not being in the TCG there is no guarantee that LTO4 tape drives will be compliant with the Enterprise specification, potentially putting any tiered storage system combining disks and LTO4 tape at a disadvantage"
Well, LTO4 products have been out there for a year or so now, and so TCG is clearly late. So it's a little a*se about face to say LTO4 is at a disadvantage!
LTO4 is also a standard agreed by several companies, following IEEE 1619.1, and using AES in a standard mode (GCM). So it's unlikely to be at any disadvantage.
Regarding "Full Tape Encryption? WTF?":
doing encryption in backup software will really hose performance. Most folks don't have servers lying around with nothing to do but compressing and encrypting bulk data sent for backup!
Doing it in hardware on the tape drive makes serious good sense. Of course, hardware compression has been on tape for a long time, and since you have to encrypt *after* compressing, so that has to be done in the tape drive too.