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Read-write media will never be as cheap as write-once-read-many media. Perhaps DVD's are on the way out, but their replacement will not come in the form of trad

Read-write media will never be as cheap as write-once-read-many media. Perhaps DVD's are on the way out, but their replacement will not come in the form of traditional USB flash drives. For example, Blu-ray discs are about $0.03 per GB, where a USB flash drive is approximately $1.00 per GB. Using flash memory for WORM style storage (like backups) is just silly.

ghshephard 15y ago
The cost differential only really makes a difference if you are backing up a lot of data - and if that's the case, you are likely backing up to a Drobo or something like that, and mirroring to BackBlaze for your offsite. Not saying _nobody_ backs up to Blu-Ray, but I'm guessing they are in the 1% of the population these days. What I'd really like, is for someone to come up with a practical form of Archival Media. Something that you could put on your shelf, and _know_ it would still be readable, 10,20,30,40 years from now. I often wonder whether these guys are for real: http://millenniata.com/ http://millenniata.com/
cabirum 15y ago
Silly? One USB drive can hold several backups, each new backup rewrites the oldest one. On the other hand, you need 30 DVDs/month (assuming daily backups, and a backup takes ~1 dvd), time to write them, and a space to store them. Also, it is way less reliable.
- oconnore 15y ago
  That scheme would be far less reliable. For one, if you corrupt a file and don't notice right away, you lose it forever (which sort of defeats the purpose of backups, doesn't it?). Also, you wouldn't actually do a full backup every day. You would perform data journaling with periodic snapshots. For example, with daily backups with a change rate of 5%, and monthly snapshots, you need only 2.5x your data size per month ignoring the minimal transaction overhead.
Terretta 15y ago
Er, tape is read write, and cheaper than your write once examples: 1600GB for $24.
- pyre 15y ago
  But how expensive is the read/write hardware?
- oconnore 15y ago
  Actually that $24 LTO U-4 800/1600GB is compressed 1600, actual 800GB, which works out to exactly $0.03 per GB (which is the same as for blu-ray).
InclinedPlane 15y ago
Never, ever, ever say "never" when it comes to tech. In 10-20 years they'll be handing out 8 GB USB drives in gumball machines for 5 cents each, and 16 TB flash drives will be $15 on amazon.
- oconnore 15y ago
  I'm not the one saying never. Why do you anticipate progress with flash storage but not with optical storage? If we have the optical technology to render a certain number of floating gate transistors in a certain area, we also have the optical technology to render 10-100x as many bits of raw data in that same area.
  - InclinedPlane 15y ago
    Optical technology has different limits than solid state technology. The "blu[e]" in blu-ray is a reference to the shorter wavelength of read lasers (relative to CDs/DVDs) necessary to cram more data on a disc. Trying to cram 100x as much data onto a single optical disc layer would require use of a laser with 1/10th the wavelength that blu-ray uses today, which would incur all sorts of additional costs and complexities. Granted, it might be possible to use other techniques (deep layering, holographic storage, etc.) to side-step such problems, but who knows what the limits are? It's telling that there isn't much research into next gen. optical storage compared to other storage forms. Additionally, increasingly people are embracing form-factors for computers that do not accommodate optical drives (smartphones, tablets, ultrabooks), which helps drive R&D money into the forms of storage that are more popular. My point is that one cannot firmly say, a priori, that one format will "never" be cheaper, larger, more popular, etc. than another. Technological progress is rapid in storage.
  - batista 15y ago
    Why do you anticipate progress with flash storage but not with optical storage? Because optical storage as a technology (R&D) has died, with optical drives starting to be removed from laptops and soon-ish desktop PCs in favor of flash, and mainly internet downloads/uploads. Bluerays are a dead end -- movie distribution will be (is) on the cloud. Ditto for music. Ditto for data. Even HDs are on the way out, to be replaced by SSDs in the coming 5-7 years.

ghshephard 15y ago

The cost differential only really makes a difference if you are backing up a lot of data - and if that's the case, you are likely backing up to a Drobo or something like that, and mirroring to BackBlaze for your offsite. Not saying _nobody_ backs up to Blu-Ray, but I'm guessing they are in the 1% of the population these days. What I'd really like, is for someone to come up with a practical form of Archival Media. Something that you could put on your shelf, and _know_ it would still be readable, 10,20,30,40 years from now. I often wonder whether these guys are for real: http://millenniata.com/ http://millenniata.com/

cabirum 15y ago

Silly? One USB drive can hold several backups, each new backup rewrites the oldest one. On the other hand, you need 30 DVDs/month (assuming daily backups, and a backup takes ~1 dvd), time to write them, and a space to store them. Also, it is way less reliable.

oconnore 15y ago
That scheme would be far less reliable. For one, if you corrupt a file and don't notice right away, you lose it forever (which sort of defeats the purpose of backups, doesn't it?). Also, you wouldn't actually do a full backup every day. You would perform data journaling with periodic snapshots. For example, with daily backups with a change rate of 5%, and monthly snapshots, you need only 2.5x your data size per month ignoring the minimal transaction overhead.

Terretta 15y ago

Er, tape is read write, and cheaper than your write once examples: 1600GB for $24.

pyre 15y ago
But how expensive is the read/write hardware?
oconnore 15y ago
Actually that $24 LTO U-4 800/1600GB is compressed 1600, actual 800GB, which works out to exactly $0.03 per GB (which is the same as for blu-ray).

InclinedPlane 15y ago

Never, ever, ever say "never" when it comes to tech. In 10-20 years they'll be handing out 8 GB USB drives in gumball machines for 5 cents each, and 16 TB flash drives will be $15 on amazon.

oconnore 15y ago
I'm not the one saying never. Why do you anticipate progress with flash storage but not with optical storage? If we have the optical technology to render a certain number of floating gate transistors in a certain area, we also have the optical technology to render 10-100x as many bits of raw data in that same area.
- InclinedPlane 15y ago
  Optical technology has different limits than solid state technology. The "blu[e]" in blu-ray is a reference to the shorter wavelength of read lasers (relative to CDs/DVDs) necessary to cram more data on a disc. Trying to cram 100x as much data onto a single optical disc layer would require use of a laser with 1/10th the wavelength that blu-ray uses today, which would incur all sorts of additional costs and complexities. Granted, it might be possible to use other techniques (deep layering, holographic storage, etc.) to side-step such problems, but who knows what the limits are? It's telling that there isn't much research into next gen. optical storage compared to other storage forms. Additionally, increasingly people are embracing form-factors for computers that do not accommodate optical drives (smartphones, tablets, ultrabooks), which helps drive R&D money into the forms of storage that are more popular. My point is that one cannot firmly say, a priori, that one format will "never" be cheaper, larger, more popular, etc. than another. Technological progress is rapid in storage.
- batista 15y ago
  Why do you anticipate progress with flash storage but not with optical storage? Because optical storage as a technology (R&D) has died, with optical drives starting to be removed from laptops and soon-ish desktop PCs in favor of flash, and mainly internet downloads/uploads. Bluerays are a dead end -- movie distribution will be (is) on the cloud. Ditto for music. Ditto for data. Even HDs are on the way out, to be replaced by SSDs in the coming 5-7 years.