Re: [MMUSIC] AD Evaluation of draft-ietf-mmusic-rfc4566bis-32

[Colin Perkins <[e-mail]>]

> On 14 Mar 2019, at 16:23, Paul Kyzivat <[e-mail]> wrote:
> On 3/14/19 11:02 AM, Colin Perkins wrote:
>>> On 12 Mar 2019, at 15:41, Paul Kyzivat <[e-mail]> wrote:
>>> On 3/12/19 7:08 AM, Colin Perkins wrote:
>>>>>>>>> This is a normative requirement of RTP, however. If we want to avoid normative examples, which I’d agree makes sense, then this needs to be rewritten as just “An RTP-based system in recvonly mode SHOULD…”.
>>>>>>>> 
>>>>>>>> That is the way it was. The change from "SHOULD" to "should" was to make it non-normative.
>>>>>>>> 
>>>>>>>> Or were you requesting to remove “e.g."?
>>>>>>> Remove the “e.g.”, yes, but also change “should” back to “SHOULD”.
>>>>>> 
>>>>>> I thought the point was that the RTP specs are normative and this is only an example, and so shouldn't be normative.
>>>>> 
>>>>> I do not have the text in front of me, but I agree that examples should not be stated normatively.
>>>> This is documenting a perhaps unexpected interaction between SDP and RTP. That is, when set to recvonly in SDP, an RTP endpoint SHOULD send RTCP. I do think that it’s important that we spell this out clearly here, with normative language.
>>> 
>>> I'm neutral here whether its normative or not. If it is to be a normative SHOULD, can we please include some "unless" text indicating the conditions when it may be omitted? Better yet, turn it into an "if NOT x then MUST ..." form.
>> I don’t think I can summarise the rules around when RTCP is, or is not, to be sent as a simple condition. If more detail is needed, I suggest “An RTP-based system in recvonly mode SHOULD still send RTCP packets as described in [RFC3550] Section 6”.
> 
> I'll put this in if it is the consensus. But this appears to give license to someone to ignore RFC3550. (I have talked to people who have said "SHOULD isnt a firm requirement so I don't need to do it.)
> 
> If that SHOULD is changed to MUST, then it will still mean that RTCP can be avoided in whatever cases RFC3550 allows. Specifically:
> 
> "An RTP-based system in recvonly mode MUST still send RTCP packets as described in [RFC3550] Section 6.”


I’m happy for you to change this to a MUST in that manner.

-- 
Colin Perkins
https://csperkins.org/