Trustworthy contacts

[Dave Howe]

From: Brian Gladman <brg@gladman.plus.com>
To: <ukcrypto@maillist.ox.ac.uk>
Sent: Sunday, September 10, 2000 9:27 AM
Subject: Re: Trustworthy contacts
> From: "George Foot" <georgefoot@oxted.demon.co.uk>
> To: "ukcrypto" <ukcrypto@maillist.ox.ac.uk>
> Sent: Saturday, September 09, 2000 11:12 AM
> Subject: Trustworthy contacts
> > A cryptosystem common to a  number of nations is impractical unless
> > those nations are fully integrated politically and have a discipline
> > which allows a full investigation by any one of them into lapses which
> > occur in any  other of them  --- a state of intimate political union for
> > which there is no prospect at the present time ?
> Not so since a number of nations already use shared cryptosystems.  Major
> nations deploy a large number of different cryptosystems and what will not
> happen is that a nation will protect its critical national information
> assets with a cryptosystem that it also shares with other nations.
  I can see relatively easy ways to do this, provided all parties use a
hybrid approach and *proven* symmetric components from the set of such
algorithms.
  Assuming this was true, then the differences would be in the PK or some
other overwrapper, protecting the session key. You could then have have *per
member* gateways that move messages and re-wrap session keys in the
propriatory format of the destination country, which would then only need to
know how to send, not to receive. they could also accept messages from the
other gateways merely to forward them onto their own net - after sanity
checking the recipient and so forth.