Re: [AVTCORE] Roman Danyliw's No Objection on draft-ietf-avtcore-multi-party-rtt-mix-18: (with COMMENT)

Gunnar Hellström <> Tue, 25 May 2021 20:42 UTC

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Subject: Re: [AVTCORE] Roman Danyliw's No Objection on draft-ietf-avtcore-multi-party-rtt-mix-18: (with COMMENT)
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Thank you for the review,

please see answers inline,

Den 2021-05-19 kl. 04:27, skrev Roman Danyliw via Datatracker:
> Roman Danyliw has entered the following ballot position for
> draft-ietf-avtcore-multi-party-rtt-mix-18: No Objection
> When responding, please keep the subject line intact and reply to all
> email addresses included in the To and CC lines. (Feel free to cut this
> introductory paragraph, however.)
> Please refer to
> for more information about DISCUSS and COMMENT positions.
> The document, along with other ballot positions, can be found here:
> ----------------------------------------------------------------------
> ----------------------------------------------------------------------
> Thank you to Rich Salz for the SECDIR review.
> ** Section 11.  Per “Participants with malicious intentions may appear ...”,
> this text seems to be describing an attacker that is party to the call.  If the
> mitigations suggested in the next sentence (i.e., secure signaling ... and
> authentication) aren’t present, this style of attack may also be possible by an
> on-path attacker as might be simple eavesdropping or injection of arbitrary
> content.
[GH] I added this sentence in section 11: "Care should be taken that if 
use of the mixer is allowed for users both with and without security 
procedures, opens for possible attacks by both unauthenticated call 
participants and even eavesdropping and manipulating of content 
> ** Section 11. Would the caution of the mixer not revealing that a user is
> hearing or speech impaired noted in Section 8 of RFC5194 apply here too?
[GH] Yes. How about inserting this sentence in section 8: " The services 
available through the RTT mixer may have special interest for deaf and 
hard-of-hearing persons. Some users may want to refrain from revealing 
such characteristics broadly in conferences. The design of the 
conference systems where the mixer is included MAY need to be made with 
confidentiality of such characteristics in mind."



Gunnar Hellström