[noise] Why no pattern omits the "ee" key exchange?

[Loup Vaillant David]

Nevermind, I forgot about forward secrecy: when both static keys are
pwned, so are the `se` and `es` key exchanges. Only `ee` provides full
forward secrecy.

Sorry for the noise,
Loup.


On Sun, 2018-11-11 at 22:29 +0100, Loup Vaillant David wrote:
> Hi,
> 
> I was just looking at the KK and IK patterns, and was wondering why
> the
> respondent was performing both `ee` and `se`.  Couldn't they just do
> `se`?  And it's not just KK and IK. *No* pattern omits `ee`.
> 
> Why?
> 
> I *guess* `ee` somehow prevents stuff like replay attacks or key
> reuse,
> but I do not see how. Any idea what I'm missing?
> 
> Thanks,
> Loup.
>