Re: [secdir] Secdir last call review of draft-ietf-perc-private-media-framework

David Benham <> Fri, 01 March 2019 20:46 UTC

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From: David Benham <>
Date: Fri, 01 Mar 2019 12:46:08 -0800
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To: Vincent Roca <>
Cc: "Paul E. Jones" <>,,
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Subject: Re: [secdir] Secdir last call review of draft-ietf-perc-private-media-framework
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Follow up question regarding your general comments on sect 8.1 and 8.2
which we have not yet addressed in -09 ;

> Attacks of section 8.1 seems more realistic to me than attacks of section
> because of a weaker attacker model: the attacker is outside of the
> and not necessarily on the path.
> Therefore I would have liked to see more details in section 8.1, that’s

You're asking for greater detail in sect 8.1 precisely because you estimate
that third-party attacks (aka outsiders to a given conference) are more
likely/common than the attacks we covered in the subsequent 8.2 section.
 Is that correct?

If so, I think we could restate some of what we have in sect 8.1 to make it
flow better and/or be clearer.   But it is not clear to us what we left out
detail-wise, or if we left out other attack examples.

With PERC's HBH integrity checks, authentication as well as HBH and E2E
encryption, we can quickly describe in text the prevention/mitigation of
attacks on the confidentiality of the media/content - PERCs reason to be -
to explain some of the brevity.

Could you help point us in the right direction with an example or two of
the things we should do to detail/elaborate sect 8.1.

> ** General comments about 8.1 and 8.2
> Insider attacks are a powerful form of attacker model with severe
> This is not a big surprise. I'd be more interesting in a detailed 8.1
> more likely to happen (weaker attacker model).

On Tue, Feb 19, 2019 at 11:13 PM Vincent Roca <> wrote:

> Hello Paul,
> Thanks for your answer and long explanations on the use of term
> « picture ». I was not aware of this
> evolution of vocabulary. Yes, please submit -09 version and I’ll have a
> new look at it.
>   Cheers,
>   Vincent