Information Security 101 - the Rules of Thumb

[James Davis]

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Peter Fairbrother wrote:

> "The chance of a secret being revealed is proportional to the square of
> the number of people who can access it; this is because the more
> possible suspects there are, the less each of them thinks they are
> likely to think they will be caught."

I don't see that this follows from your explanation. Isn't it true if,
and only if, your perception of the likelihood  of being caught varies
linearly with size of the group? I'm not sure that's always true. If
you're going to be this specific, there ought to be a rigorous explanation.

(I'm also confident that it's possible to design a scheme for the
sharing of secrets in which it's possible to tell who disclosed the
secret. If the group knows this ...)

James

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