potential new IETF WG on anonymous IPSec

[Hadmut Danisch]

On Mon, Sep 13, 2004 at 02:41:21PM -0400, Sam Hartman wrote:
> 
>     >> No.  opportunistic encryption means I have retrieved a key or
>     >> cert for the other party, but do not know whether it is
>     >> actually the right cert.
> 
>     Tim> If the key is retrieved from the other end of a TCP
>     Tim> connection (like vanilla ssh works the first time), is that
>     Tim> included within the definition of "opportunistic encryption"?
> 
> Yes.



Be careful. I believe that this is not as simple. It depends on 
what you use the key for.

If it is used for encryption, then something like "opportunistic
encryption" exists. After all, using an unverified key for encryption
is not yet worse than using no encryption. So even if the key might 
be the attacker's one, nothing is lost compared to plain
communication. 

But avoiding faked TCP resets is also a matter of authenticity. 

Does 'opportunistic authentication' exist?



regards
Hadmut

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