Re: Question on transport protocol

["Richard E. Silverman" <res%shore.net@localhost>]

On Tue, 15 Jan 2002, Derek Fawcus wrote:

> Or is the intention that if a non DH exchange is used,  then this delay
> is required (i.e in the more general case).

Exactly.  In your next post, you write:

> The obvious problem with implicit server authentication is that it
> leaves one open to a MITM attack...

This doesn't make sense, as a big objective of anything called "server
authentication" is exactly to *prevent* MITM.  Perhaps you have some model
of implicit authentication in mind, but the spec does not specify a
mechanism for "implicit server authentication."  The idea is merely that
it might happen as an integral part of some future key-exchange method,
which could then do without explicit server auth mechanism described here.
For examples, see the server auth method of SSH-1, as well as the
proprosed GSSAPI/Kerberos method for SSH-2.

-- 
  Richard Silverman
  slade%shore.net@localhost