Re: [saag]: Review of: Opportunistic Security -03 preview for comment

Paul Wouters <paul@nohats.ca> Fri, 22 August 2014 14:13 UTC

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Date: Fri, 22 Aug 2014 10:13:28 -0400
From: Paul Wouters <paul@nohats.ca>
To: saag@ietf.org, ietf@ietf.org
Subject: Re: [saag]: Review of: Opportunistic Security -03 preview for comment
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On Fri, 22 Aug 2014, Viktor Dukhovni wrote:

> On Fri, Aug 22, 2014 at 05:25:17AM +0000, l.wood@surrey.ac.uk wrote:
>
>> Okay, so with opportunistic security, all a man in the middle
>> has to do is block any communications he can't decrypt, and it
>> automatically downgrades to select something he can break?
>
> And without OS, he need not do anything at all, because the vast
> majority of the traffic is cleartext.  However OS can support
> downgrade resistant modes of operation, given appropriately secure
> out-of-band signalling, (possibly DANE/DNSSEC).
>
> OS is not an effort to displace already working authenticated
> encrypted traffic.

What this little exchange above here shows is that people involved in
this dicsussion _still_ don't know whether "OS" is just the anonymous
crypto or whether includes the "design pattern recommendation advise"
of using authenticated encryption if available.

If the people who agree to "just publish it" cannot even keep their
usage straight, I'd say the document needs more work.....

Paul