6
1
Do you know if exists a write-once-read-many (aka: WORM) USB flash or SD memory?
I need an electronic write once memory to meet law requirements for storing sensitive data, and I want an alternative to my actual solution of CD-R discs.
I found that SanDisk produced some WORM SD card, but now this kind of card seems to be out of production.
Tobia
Posted 2014-06-22T09:54:56.467
Reputation: 2 022
1
Given that DVD/CD drives are now more often external and connected via USB, they do not conflict with your request for an alternative.
I agree that CD-R discs are not ideal, especially after having a couple go bad on me after a few years. But you could instead upgrade to the compatible M-DISC, where M stands for Millennium.
While I don't know if an M-Disc will really hold for a thousand years, or that anyone will care about your data at that time, M-Discs have become much cheaper in the last few years. For example on Amazon, Millenniata 4.7GB M-Disc Write Once and Read Forever, Read 16x/Write 4x Speed, 50 Pack goes today for $124.95. You can also today find Blu-ray M-Discs.
You would have to choose carefully your DVD/CD drive for compatibility with M-Discs. I have found this M-Disc's list of devices that can write, but I cannot vouch for its completeness.
If you wish to go up another notch, you could pass to WORM tape cartridges, but there you are multiplying the price-tag by a factor of 10.
SD WORM cards seem to have gone out of fashion, while Flash-using WORM seems not to exist. So as far as I can see, the options that are left are CD-R, M-Disc or tape.
harrymc
Posted 2014-06-22T09:54:56.467
Reputation: 306 093
One big limit is that a CD/DVD has 99 tracks so after 99 writes I have to change it... This is my actual solution but I'm looking for alternatives. – Tobia – 2016-02-06T13:52:16.740
The problem is not the size ( I have to store only few KBs per day) the problem is how many session I can open. For example CD discs can have only 99 sessions. If I write 99 times 1MB I have only 99MB used but I cannot open another session. For Dvd is the same. – Tobia – 2016-02-06T15:31:29.210
This document says "more than 300 tracks can fit into the width of a single strand of hair on the Blu-ray Disc", which means a huge number of tracks. To be sure, and if you have access to a Blu-ray capable writer, you could invest in one ordinary Blu-ray disc to find out how many tracks/sessions it can hold - M-Disc will be the same. Otherwise, only tape is left, but it is costlier.
– harrymc – 2016-02-07T13:15:54.3570
For flash based memory I can't seem to find anything either. This talks about writing to the ones you're talking about but that doesn't get you any.
You could use a software to make a USB drive read-only like this one Softpedia download, but software is breakable and a fat32/64... system might not even recognize that there is security and go right through. The other recommendation would be to get one of the flash cards that has the lock switch, write your data, lock it, then break the toggle off... still, someone could probably switch it back with a paperclip or something.
Cand3r
Posted 2014-06-22T09:54:56.467
Reputation: 2 629
The switch on the side of memory cards (at least SD cards, maybe others) is a lot like the tabs on the bottom of a cassette tape. The switch on the side of the card simply tells the reader whether or not it is supposed to writeo, without actually changing anything electrically on the card. Modifying a reader to ignore that pin effectively makes every card inserted writable. – isaacparrot – 2018-03-04T03:12:26.220
0
Have you considered something like DLT, which has WORM media available?
DLT tapes have WORM media, but you might not have the option to add a DLT tape drive to the systems you're working on. You could probably find a DLT system that supports WORM for relatively little money these days, since LTO has mostly taken over for DLT.
It may also be worth noting that LTO has WORM media available as well, starting with LTO-3.
NDC
Posted 2014-06-22T09:54:56.467
Reputation: 106
I never tried DLT, do you think it is better/faster then burning a CD? – Tobia – 2016-02-12T07:30:12.487
It's certainly not going to be faster, as the tape needs to seek to the writable area, which gets further away from the beginning of the tape each time you write to it, and it needs to be rewound before it's ejected. That said, the time to do that is not obscene, and might be faster than it sounds. "Better" is a value judgement, I can't say whether it's better or not for your particular scenario, but I'd encourage you to investigate it. At very least, it's provably WORM, as opposed to flash-based methods. – NDC – 2016-02-12T21:18:51.230
-1
There is a company that may provides the WORM Card like solution. This company is called Embestor. They provide customized service.
Josh Dallas
Posted 2014-06-22T09:54:56.467
Reputation: 1
1Welcome to Super User! Thanks for your contribution. Providing the link to the company's website would be a good improvement to this answer. – robinCTS – 2018-07-06T08:39:21.790
1Nobody knows any alternative to CD-R? – Tobia – 2016-02-05T18:42:56.083
http://greentec-usa.com/wp-content/uploads/2015/04/WORMdisk-Two-Page-Overview.pdf for bigger data. i have found anything for smaller like you want. Im sure you could invent something to do the trick. – NetworkKingPin – 2016-02-05T19:03:25.293
Have you considered storing your data in a cloud? I'm sure you can find providers who can prove the upload date of your files and whether they have been changed since upload. – Máté Juhász – 2016-02-06T12:43:42.003
It is a good idea but the law requirement asks for a local copy of worm backup. – Tobia – 2016-02-06T16:41:14.600
@Tobia you may want to see if one of my previous answers to a similar question is something you'd be interested in.
– Vinayak – 2016-02-08T06:48:23.180@Vinayak surely I will try to contact them, but worm seems not to be listed in the options. – Tobia – 2016-02-08T07:19:42.787
@Tobia From maikii.com:
– Vinayak – 2016-02-08T07:58:15.113Non-erasable data: When loading non-erasable data, your files are inserted in a partition of the chip, which is separate from the free memory so that it will not get erased even if formatted. When inserting the peripheral device into the computer, two icons will appear: one is read-only and the other is mass removable memory, which can be used freely. It is possible to load any type of data or file. It is only compatible with Windows.Isn't that what you're looking for?No, write-once-read-many means that you can write when you want and append data to the memory (like a CD) but you cannot delete what you wrote. Non-erasable in this case means also not writable by user... – Tobia – 2016-02-08T13:50:27.873
@Tobia This probably isn't what you want but I think the Memory Vault flash drive from SanDisk is kind of a WORM storage in that it becomes read-only after the available storage is full or after certain pre-determined erase and refill limit is exceeded.
– Vinayak – 2016-02-09T17:55:22.207I saw this products, but unfortunately it is not WORM becase you can write and after a second erase your file. Maybe if you write at once all storage space available it can be considered WORM because is becames read-only immediately... but this is not my case, I have to write few KB daily. – Tobia – 2016-02-09T18:02:08.337
Maybe you could try contacting them at OEMSales@sandisk.com and see if they can get you what you need. According to this press release their WORM SD cards are available in 1 GB capacity worldwide.
– Vinayak – 2016-02-09T18:30:07.363This worm card from SanDisk seems to be a never-started project. I was able to get one of them, they needed a custom SD reader and a library to write in, but I left this cards when I understood that these are not produced anymore. – Tobia – 2016-02-09T18:57:24.093
(i wrote about them in the end of my question) – Tobia – 2016-02-09T18:58:30.067