[Cryptography] Explaining PK to grandma

[Kristian Gjøsteen]

26. nov. 2013 kl. 17:46 skrev Jon Callas <jon at callas.org>:

> On Nov 26, 2013, at 6:15 AM, Kelly John Rose <iam at kjro.se> wrote:
> 
>> 
>> The missing piece here is you can copy such a signature with a good forger. Public key makes it so copying a signature requires something more. 
>> 
>> I think signature is a misnomer in this circumstance.  
> 
> Yes, "signature" is an unfortunate term. "Seal" would have been better.

I like seal. The seal is a thing clearly separate from you, just as the signing key is not inside your head.

Cryptographic signatures can be considered impossible-to-forge seals.

This makes it meaningful to talk about someone stealing, copying or misusing the seal (the signing key). You can even reason about placing your seal into a trusted locker in your local bank (your bank stores your signing key for you) or giving it to your secretary along with the authority to use the seal whenever you tell him to (inserting your smart card into your computer). Now you can explain all kinds of interesting trust situations in an intuitive way.

I like seal.

-- 
Kristian Gjøsteen