The cr.yp.to microblog: 2018.04.23 02:00:11

2018.04.23 02:00:11 (988205858587897856) from Daniel J. Bernstein, replying to "Frédéric Grosshans (@fgrosshans)" (988019591958974465):

Are you capable of defining your concept of security for exchanged keys _without_ making ad-hoc references to the particular structure of QKD as part of the definition?

Context

2018.04.13 21:55:56 (984882899169284096) from Daniel J. Bernstein, replying to "Frédéric Grosshans (@fgrosshans)" (984299450360324101):

So you think that crossing out the word "absolute" would change the meaning of the claim that QKD exchanges "a cryptographic key between two remote parties with absolute security, guaranteed by the fundamental laws of physics", so it would no longer be clearly false advertising?

2018.04.19 19:03:41 (987013879338340353) from "Frédéric Grosshans (@fgrosshans)":

Exactly. The “laws of physics” indeed guarantee the security against attacks on the channel, under the standard assumption (which has to be clear to the reader) that no other leakage happens, that the apparatuses indeed work as advertised and modelled.

2018.04.21 13:00:52 (987647350540730369) from Daniel J. Bernstein, replying to "Frédéric Grosshans (@fgrosshans)" (987013879338340353):

So you think that "absolute security" of an exchanged key means that it's safe against all attacks, but crossing out the word "absolute" means that it's referring only to attacks intercepting the photons in the particular key-exchange protocol you have in mind?

2018.04.22 13:40:01 (988019591958974465) from "Frédéric Grosshans (@fgrosshans)":

By standard QKD model, I mean the adversary: - has access to all classical communications and unlimited computing power - can perform arbitrary interaction with the quantum pulses The apparatuses are supposed to be well modelled physically and well shielded.