Alright, it might already exist, or it can be total bs, any opinions are welcomed.

The problem:
CDs, DVDs are a popular medium to backup data, but they are not as reliable as some would expect. A scratch, some unforeseen situation (instable molecules in some earlier CDs) can render them useless, and as such your burning application is the same as pressing the delete button.

The idea:
for hard drives RAID systems are well known for data protection. RAID5 does the following: you have a bunch of devices of the same size, say 3. You get a 4th, and you put a check sum of all the data on the other 3 onto it. This way if any of the 4 is damaged or lost, you can recreate the missing one from the other 3 (it can work with different number of devices, but the possibility of recovery will change). So if you have 3 DVDs, make an application that will create a backup copy of all of them onto a 4th.
Easy as that.

Anyone interested? I was thinking about an open source project with no special platform in mind. Creating an ISO image is probably the best way to go, that can be burnt by a platform specific application.





The idea is inspired by the simple fact, that I have lost several GB of data due to such "happenings", but the falling price of these media is tempting, although I am still not likely to backup everything twice.

I am not likely to have time to code it myself, but I am here to help and organize things

With the low cost of hard drives at this time, I would feel much safer using a raid 1 setup with 2 or 4 hard drives that creates an automatic backup to a separate hard drive. This way you always have a backup that is independent of your windows drive or drives if you have setup multiple drives in an array.

You are correct in that Cd's/Dvd's are popular but most heavy users can tell you that this type of media Is by no means Reliable. I would not recommend using either of these as any type of backup for the long term. You can be fairly sure that within a few years there will be no way of reading or using this type of media because technology is changing so fast and most media today will probably be unreadable in the future. Beta max was the greatest thing a few years ago but just try to read this media/format today and you will see what I mean.

I spent a great deal of time converting old 8mm films to digital and from my research I found that the most reliable backup is Film. This is the ONLY media that is guaranteed to be readable after 100 years or more. All new movies produced by the big studios are backed up or archived on actual film because this method is guaranteed to be usable forever if properly stored.

There is no digital media right now that has passed the test of time and therefore by saving an image gives you no guarantee of usability in the future. Flash scares the heck out of me for the future. I compare flash to floppy disks. As many people already know, most floppy disks are unreadable after a few years for various reasons and all data contained is lost.

The best way to backup at this time that I can see is a raid 1 system using a separate hd for each hd used to preserve the data in its actual form that it was created and also keeping any and all software that you used to create your files. Do not stripe any data (ie using 1 hd for a raid 1 system) but instead use 2 hd's or 4 etc with a complete automatic backup to a separate drive. I would be a little concerned if I used a raid 5 configuration due to whether or not I could actually use those files in the future.

This was a great topic that you started because from my experience in the past, most people never took this into consideration and there has been very little discussion about this in the past 10 years. A few years ago when I began backing up older 8mm film and super 8 film I thought I was behind the times and actually I was so far ahead that I ended up at the top of googles search list for a long time because so many people were/became concerned with backups that would last forever. (too bad that money was not a concern because getting on top of the search engines is how you get very wealthy on the internet LOL).

Here is the real solution:

Safe Storage for 1400 Years

From my own experience, I agree with you. Right now I use hard disks as backup, although I stick with RAID5. I haven't backed up anything to CD/DVD for 5 years, because some of my old discs were dead.
For most of the things I would not think about really long range archival. I think it only makes sense for personal things, like family photos and videos. For such things RAID1 is great, since the size is not too big, so the cost stays reasonable.
For anything that you get from outer sources like music, movies, etc, a mid-range solution is just enough, because not just the storage medium, but the data format AND quality is changing really fast (VHS-> HD), so even if you skip some of the changes, sooner or later you'll have to get the whole thing again.
What I aim to do here is finding a solution for archiving data falls into this latter category, and I think using CD/DVD/Blue-Ray with some added protection might be optimal.
The Pergamum project is interesting, I've read about it earlier, but I think I'll wait a bit before building one for myself

I don't exatctly remember the name of the project, but there was a nice one, drawback is it can only be written once.

It used small DIODES to store one bit.

It works by applying high voltage to BURN the diode if logical zero, and verify connection if logical 1.


The density of the stuff is a lot more higher than todays memory solutions, does not need electric power to storethe data.

It can only be written one time, no modifications later.

When manufactured all diodes are tested if they are conductive or not.
If all diodes pass the test, the stuff can be writted.

High enough voltage is able to ruin the diode, so it will not conduct electric power anymore.

Read spead of the thing is HIGH, no need to wait for the memory.
So basicly the concept was like a hitload of small switches.

"0" if its open, "1" if closed.


Some memory types use 6 transistors / bit, this solution uses 1 DIODE /bit.

Compared to them up to 10 times higher density can be achieved.

I dunno why was the project halted, all I know is te technology is only able to be written once, and thats all. Have high read speeds,
and is like a passive circuit.

Time it can preserv data was rated higher than 1000 years,and do to high component density it would be a cheap solution. Verry cheap.
BUT after a full write the datablock would had to be verifyd, and on fail the thing had to be replaced.

As far as I know, it where ment to produce long lasting electronic librarys.
Was some kind of russian stuff, I think russian things are.. Brute, RAW, ugly, stupid, but they do the job well...
Simplicity, and "goal oriented" design is a signature of russian things, wish Icould remember the stuff better..

IBM has some sorth of technology simular, they call it Efuse.
Basicly it is inside special processors they make, and fuses can be "blown" to swich bit 1 time. It is included in xbox360 security schema,
thats why I know it. But as far as I know "fuses" are bigger than a simple diode.

I only wrote the xbox example to show that a technology like I described allready exsists in production, and I think long term archives are going to be useing this type of methood.
Since the reading of the bits needs only a verry lov voltage, and the memory has a power consumption allmost ZERO, and great response times (equal to diode opening speed allmost) it would be a verry fast type to read.

Well, thats what I know about projects in long term low cost, low maintainance archiveing.
Since there are no active components in the memory storeing data, except the diodes, with change of the controlling unit the speed of the memory depends on the controller.

Realy have no clue what happend to the design.