Is it possible to make a USB key readonly ?

[stlaural]

As I don't care about the programing language that would be use I thought I could just post this is the Chit/Chat section.

I've been thinking about this for a while and I really wonder if what I'm asking here is even possible.

Let's say I want to distribute some data on a USB Key, that I bought bought as I'm not a manufacturer, I don't want anyone on any computer to be able to modify the content of the USB device. I don't care if they copy what's on the device but I don't want them to be able to change it or copy something new on the key. How would someone do this ? How can I insert a program on the Key that would make sure that, unless you know the password the data is not altered. But the data needs to be readable at all time. Also need to make sure that the application doing that job cannot be deleted from the device

I already know that you can play in the registry add add some key to disable writing to external device but this only apply to the machine and not to the device itself so its not a good solution for what I'm looking for. I know that there are USB device with a lock switch but any user could just slide the switch so its not a solution.

I'm really looking for a software solution here.

Any suggestion is welcome !

[pcuser]

I know that there are USB device with a lock switch but any user could just slide the switch so its not a solution.

Super glue?

[stlaural]

Super glue?

Yeah, but the distributer needs to be able to write to it, using a password for example.

Nice try

My own conclusion is that its not possible unless I was the manufacturer of the Key. This way I could add a readonly chipset between the USB connector and the Memory chipset that manage the writing.

[techgnome]

You went wrong on two accounts. 1) Posing in the Chit-Chat section ... what you really want is the General Developer section. Your second mistake was not putting [Serious] tag around the title, while posting in Chit Chat...

I'll ask a mod to move it before too much damage is done.

-tg

[wossname]

Anyone with linux root privileges can take a full image of any USB disk and then rewrite it as they see fit, thus rendering any attempt at write protection futile. I suggest linux as an easy example, all Unix variants can do this. Windows and mac users will have more trouble because they are mindless slaves.

[Shaggy Hiker]

What you would probably need would be a ROM chip with a USB interface. Making such a thing your self would be impractical as it would tend to be a giant monstrosity, but there are companies out there that prototype things like this, so you might shop around.

[si_the_geek]

Thread moved to 'General Developer' forum.
(thanks for letting us know TG )


A few years ago I saw a company that sold "write-once" USB sticks, which acted like normal ones until you ran a program that came with it - and that program caused minor physical damage which permanently disabled the writing mechanism. The price was pretty reasonable, but unfortunately I can't remember the company or product name.

[baja_yu]

Thread moved to 'General Developer' forum.
(thanks for letting us know TG )


A few years ago I saw a company that sold "write-once" USB sticks, which acted like normal ones until you ran a program that came with it - and that program caused minor physical damage which permanently disabled the writing mechanism. The price was pretty reasonable, but unfortunately I can't remember the company or product name.

Took your idea and googled "write once flash memory" and got this http://www.engadget.com/2007/11/20/1...-to-cost-5-99/ and this http://en.wikipedia.org/wiki/Write_Only_Memory

[stlaural]

You went wrong on two accounts. 1) Posing in the Chit-Chat section ... what you really want is the General Developer section. Your second mistake was not putting [Serious] tag around the title, while posting in Chit Chat...

I'll ask a mod to move it before too much damage is done.

-tg

Right I should have thought about the General Dev Section, thank you TG.

Anyone with linux root privileges can take a full image of any USB disk and then rewrite it as they see fit, thus rendering any attempt at write protection futile. I suggest linux as an easy example, all Unix variants can do this. Windows and mac users will have more trouble because they are mindless slaves.

Yeah but it is for windows user and I really don't think they would think about that

Thread moved to 'General Developer' forum.
(thanks for letting us know TG )


A few years ago I saw a company that sold "write-once" USB sticks, which acted like normal ones until you ran a program that came with it - and that program caused minor physical damage which permanently disabled the writing mechanism. The price was pretty reasonable, but unfortunately I can't remember the company or product name.

We need to have a way to write again on the key by providing a password or something to update data on it. we just don't want any user to put anything on it.

Thanks for moving the thread.

[stlaural]

What you would probably need would be a ROM chip with a USB interface. Making such a thing your self would be impractical as it would tend to be a giant monstrosity, but there are companies out there that prototype things like this, so you might shop around.

I'll sure see what I can find on that.

[Shaggy Hiker]

Some of the PROM chips can be wiped and re-used. The password is always the same, though: UV light of the right wavelength.