Re: [AVTCORE] Kathleen Moriarty's No Objection on draft-ietf-avtcore-aria-srtp-10: (with COMMENT)

Kathleen Moriarty <> Thu, 03 August 2017 02:50 UTC

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From: Kathleen Moriarty <>
Date: Wed, 2 Aug 2017 22:50:02 -0400
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To: Ben Campbell <>
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Subject: Re: [AVTCORE] Kathleen Moriarty's No Objection on draft-ietf-avtcore-aria-srtp-10: (with COMMENT)
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Hi Ben,

Thanks for the quick response, inline.

On Wed, Aug 2, 2017 at 10:36 PM, Ben Campbell <> wrote:
>> On Aug 2, 2017, at 8:50 PM, Kathleen Moriarty <> wrote:
>> ----------------------------------------------------------------------
>> ----------------------------------------------------------------------
>> Although this is not a discuss, I think updated text would be very helpful on
>> the following two issues.
>> I agree with the SecDir reviewer that there should be more text around the
>> short tag length in the security considerations section.  I don't see a
>> response to that post though.
> Hi Kathleen,
> I think you are referring to Ben Laurie’s SecDir review of 06, rather than his later review of 09. Is that correct? Version 9 removed the GCM_8 modes. Or were you referring to something else?

I am referring to Ben's review of -06, where he had the following text:

Thirdly, I am not familiar enough with SRTP to understand why short
authentication tags are needed, but in general its a bad idea, so I
feel the Security Considerations should explain more fully than
"Ciphersuites with short tag length may be
   considered for specific application environments stated in 7.5 of
   [RFC3711], but the risk of weak authentication described in
   Section 9.5.1 of [RFC3711] should be taken into account."

I don't see an update to this text to address his question - providing
additional information as to what should be "taken into account".

>> For SHA-1, a reference to RFC6194 for the security considerations for
>> SHA-1message digest algorithms would be helpful. Thank you!
> Thanks, that’s helpful. I agree the security considerations needs to say something about the use of SHA1

Great, thanks!
> Ben.


Best regards,