Analogien um das Prinzip von PGP zu erklären

[Robert J. Hansen]

> I seem to recall someone on this list using a mailbox like the one at
> [1] as an analogy for public-key encryption: anyone can walk up to the
> mailbox and place a letter in the slot ("encrypting a message to the
> recipient's public key"), but they cannot retrieve any other letters in
> the box [2].

'Twas me.  :)