[Cryptography] (no subject)

[Bear]

On Sun, 2013-11-24 at 13:31 +0100, Eugen Leitl wrote:
> On Sat, Nov 23, 2013 at 09:45:18PM +0100, Ralf Senderek wrote:
> 
> > 1) The concept of asymmetric key is unexplainable to your granny.
> >

I'm pretty firmly of the opinion that your grandparents ought not be
required to understand asymmetric key crypto in order to use it. 

They need a little appliance next to the computer that's shaped and 
painted like a little mailbox with a USB socket inside a great big 
keyhole on the front and another USB socket inside the mail slot.  

Then you give them a USB stick with a picture of a key printed on 
one side and a picture of a stamped envelope on the other. 

"When you want to read your mail, unlock the mailbox by putting this
key into it...  then you can bring the mail into your computer, just
like bringing paper mail into the house.  You read and write your 
mail on the computer ... and finally you take the mail out of your
computer and put it into the mail slot to send your mail...."

"Oh, yeah, if you want to get your email anywhere else, you need to 
take the mailbox and the key with you.  And when you're done remember
to clear your mail off their desktop, you don't want to leave a mess."

You and me and the guy who manufactures those mailboxes know there's 
public-key crypto going on inside the appliance, and a whole lot of 
filtering to make absolutely sure no 'scripty' stuff is going onto 
that USB stick.  Trying to explain it to anybody else is a waste 
of time.