CDR: Re: Public Key Infrastructure: An Artifact...

[Bram Cohen]

On Fri, 24 Nov 2000, John Kelsey wrote:

> At 04:47 PM 11/22/00 -0800, Bram Cohen wrote:
> 
> >Once again, the solution to the problems of offline
> >operation appears to be online operation.
> 
> And the annoying thing about this is that once we go to
> needing an online trusted third party to allow us to have
> secure communications, we may as well chuck the public key
> stuff and just use symmetric ciphers and the key exchange
> protocols worked out ten or fifteen years ago.

That isn't completely true - using public key protocols involves many
fewer messages total, and allows for much more decentralized data access -
we're using it for Mojo Nation for precisely those reasons, and it's made
a fundamental difference in scalability.

It isn't quite as revolutionary as one might expect though.

PKI for contracts and treaties is also largely overhyped - those have long
depended on agreements being widely distributed/notarized/timestamped for
their reliability, and the law of contracts is all based on oral
agreements. PKI just contributes a bit more evidence (and, apparently, not
a crucial part) and making it be a 'legally binding signature' mostly has
to do with the technical question of when an agreement goes from being
negotiated to legally binding. Sending a piece of mail saying 'ok' can
work just as well.

-Bram Cohen