Re: [Bug-xorriso] BDXL support

[Johan de Jong]

Hi,

On Fri, Jan 15, 2016 at 9:57 PM, Thomas Schmitt <address@hidden> wrote:

Hi,

Johan de Jong wrote:
> the current consensus is that degradation or organic dyes
> results in corruption in a few years or sometimes months

I have to disagree. Once written and verified, optical media
seem to stay readable for at least a decade.

I can live with that. But studies indicate that BD LTH media should be avoided in that case. BD HTL media supposedly fares much better. Perhaps M-disc is just overkill and I should just drop it.

> [future] optical drives hard to come by and the data needs
> to be migrated

I am very optimistic about future availability of reader hardware.
Data CDs are around since about 20 years and still readable by
all optical drives. My old 500 MB QIC tapes from the 1990s
lost their reader hardware ten years ago, when the Ultra SCSI
controllers had been pushed aside by IDE which already became
replaced by SATA. You need a complete old computer to read
such stuff.
With CD you just need to buy a drive that matches your current
computer.

Agreed. But the number of manufacturers that still produce burners/readers is significantly decreasing the last few years. In 2015 only LG, Samsung and pioneer were left. And those that do are moving towards external drives. Signs are that it is becoming a niche market. Perhaps there will be a new surge if BDXL gains momentum in the wake of 4K screens and 4K BDXL media, but it looks like optical is moving towards being a small market for people who use it for backup purposes. For all other purposes external drives, a NAS or cloud storage appears to take over. If the markets narrows significantly it may have impact on prices, quality and over the years even availability. Time will tell, but I hope you're right.

 

If you use optical media for archiving and delete the original
data on hard disk, then you should have several identical copies
and checkread them once per year. As soon as the first copy
fails, make more copies of the still good ones.

If the optical media serve as backup, then have more than one
of them. Not necessarily identical ones.
If there are several incremental backup levels then especially
checkread the older ones from time to time. In case of decay,
make new updates from the level before the oldest bad level.

Makes sense. Good advice.

Have a nice day :-)

Johan