Break-Open One-Shot Password Stores

Paul Barnfather lists at
Mon Feb 27 11:00:17 GMT 2012

On 27 February 2012 07:42, Ian Batten <igb at> wrote:

> Has anyone seen such devices for sale?

How about the way banks issue PIN codes for ATM and credit cards? They
come in the form of a printed letter with a neat little plastic
tear-off tab which makes it very clear if the PIN has been read by
someone else.
They seem to be a cheap and effective way of storing and communicating
a "read once" password.

I assume they are fairly resistant to casual tampering.

Does anyone know if they are printed with a conventional printer, or
do they require specialised hardware to produce?

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