Re: [dane] [saag] Need better opportunistic terminology

[Nico Williams <[e-mail]>]

On Wed, Mar 12, 2014 at 11:49 AM, Joe Touch <[e-mail]> wrote:
> On 3/12/2014 6:35 AM, Stephen Kent wrote:
>>>> I have
>>>> suggested "opportunistic keying" as a preferred term, since its the
>>>> key management, not the encryption per se, that distinguishes other
>>>> proposed modes of operation for IPsec, TLS, etc.
>>>
>>> I agree if you're replacing OE with OK ;-)
>>
>> yeah, I like OK (and I like IKE too, for those of us old enough to
>> appreciate that election slogan)

OK will present difficulties as an acronym...  Otherwise I like
"opportunistic keying", but it could cover a large range of behaviors
(e.g., TOFU).

> I'm still a little hesitant, thinking on it further, about the term
> "opportunistic" in this sense at all.
>
> BTNS uses unsigned key exchanged, and there's nothing "opportunistic" about
> it. Unsigned authentication is the goal from the start.

For me the goal was to use channel binding at the application layer.
But we never got there: no one seems to care much about end-to-end
IPsec, sadly.  (Well, it's not that no one cares, but that it's too
late now; TLS is king.)

> OE as defined in RFC 4322 isn't about using unsigned key exchange; the
> "opportunistic" sense is derived from using keys retrieved from DNS without
> prior agreement. That's not what happens in BTNS.

Stephen has it right: OE in the RFC4322 sense is about applying
protection even when SPDs don't agree on this, but it still requires a
keying infrastructure (i.e., trust paths).

Nico
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