[noise] non replayable XK/KK?

[Justin Cormack]

On 28 January 2018 at 18:12, Justin Cormack
<justin at specialbusservice.com> wrote:

> 2. DH early DH often rule: always do a DH as soon as you can

Actually that rule is not quite right.

But I think only your XKdefer1 is actually usefully different, so XK
has three usefully different
versions, normal defer and early:

XK(s, rs):
  <- s
  ...
  -> e, es
  <- e, ee
  -> s, se

XKdefer1(s, rs):
  <- s
  ...
  -> e
  <- e, ee, es
  -> s, se

IK(s, rs):
  <- s
  ...
  -> e, es, s, ss
  <- e, ee, se