Re: [AVTCORE] Fwd: RTP payload format type registry vs. MIME-type registry

Hi,
I agree with what Magnus suggested. I was part of the discussion in the past
Roni Even

On Mon, 9 Oct 2023 at 13:05 Magnus Westerlund <magnus.westerlund=
40ericsson.com@dmarc.ietf.org> wrote:

> Hi,
>
>
>
> The RTP Payload Format Media Types is a mostly redundant registry, in that
> its only purpose is to help determine which media types that has RTP
> Payload formats. Already prior to RFC 8088 was written we had discussion
> about this registry and if we should kill it. We didn’t do that at that
> time, and the best we could do in RFC 8088 was to be very clear that you
> need to ensure that it is registered there also. However, as noted it has
> been forgotten several times, as the media type registry is what is
> actually relevant to register.
>
>
>
> I would think a reasonable way forward is to actually close the registry
> and update RFC4855 and RFC 8088. When closing this, one could consider to
> clean up the registry up to the date of closing by adding the missing RTP
> payload format media types that have been missed. But, unless someone knows
> of someone externally depending on this registry, to avoid future issues,
> and also be able to make a clear comment that this registry is not relevant
> in a note, writing a document killing it is likely an easy way forward.
>
>
>
> Cheers
>
>
>
> Magnus
>
>
>
>
>
> *From: *Stephan Wenger <stewe@stewe.org>
> *Date: *Wednesday, 4 October 2023 at 15:43
> *To: *Bernard Aboba <bernard.aboba@gmail.com>, IETF AVTCore WG <
> avt@ietf.org>
> *Cc: *Harald Alvestrand <harald@alvestrand.no>, Magnus Westerlund <
> magnus.westerlund@ericsson.com>
> *Subject: *Re: [AVTCORE] Fwd: RTP payload format type registry vs.
> MIME-type registry
>
> Hi,
>
>
>
> Copying specifically Harald Alvenstrand (as Mediaman chair) and Magnus
> Westerlund (as RFC 8088 author)
>
>
>
> I’m an arguably experienced payload format author, but know little about
> IANA mechanics, and care even less.  I’m sure I’m not alone with respect to
> the latter.  People like me will need a template and guidance from which we
> can copy-paste-adapt in the future.  I don’t know who can provide that
> guidance, but frankly, I don’t believe AVTcore is the right group to
> provide it, simply because we didn’t get it right so many times in the
> past.   I also don’t think we can rely on guidance by the IESG or the media
> type review people without specifically asking.  They didn’t spot problems
> in the past, either.
>
>
>
> I have no idea on how to arrive at that suggestion, though W3C identifying
> and Bernard and Jonathan taking ownership of the problem by at least
> describing it clearly is an excellent first step.  Maybe move the
> discussion over to the media-types list?  Or Mediaman could help?  Once we
> have the sentence or two needed, the EVC payload could be used as a test
> case as it is in the right stage of the process to see results quickly.
>
>
>
> Then, I would suggest revising RFC 8088 and specifically section 7.4.  (In
> a revised RFC 8088, we should also insert a section dealing with normative
> references to media codec specs, as this has been another recent pain
> point.)
>
>
>
> Stephan
>
>
>
>
>
> *From: *avt <avt-bounces@ietf.org> on behalf of Bernard Aboba <
> bernard.aboba@gmail.com>
> *Date: *Tuesday, October 3, 2023 at 16:59
> *To: *IETF AVTCore WG <avt@ietf.org>
> *Subject: *[AVTCORE] Fwd: RTP payload format type registry vs. MIME-type
> registry
>
> On August 29, 2023 a post to the W3C public-webrtc mailing list pointed
> out an issue with IANA RTP payload format type registrations:
> https://lists.w3.org/Archives/Public/public-webrtc/2023Aug/0033.html
>
>
>
> The RTP payload format registry, which is referenced by the W3C WebRTC-PC
> specification, omits entries for widely deployed video codecs, including
> VP8 (RFC 7741), HEVC (RFC 7798), VVC (RFC 9328) and AV1 (
> https://aomediacodec.github.io/av1-rtp-spec/
> <https://protect2.fireeye.com/v1/url?k=31323334-501cfaf3-313273af-454445554331-db3c9ccec786cf77&q=1&e=bcb5dc8f-c55e-46ea-a97e-9f83e105e745&u=https%3A%2F%2Faomediacodec.github.io%2Fav1-rtp-spec%2F>
> ):
>
>
> https://www.iana.org/assignments/rtp-parameters/rtp-parameters.xhtml#rtp-parameters-2
>
>
>
> However, the IANA mime-types registry (see “video”) is more complete,
> including entries for the missing codecs:
> https://www.iana.org/assignments/media-types/media-types.xhtml
>
>
>
> At the IETF AVTCORE WG interim meeting on September 26, the WG discussed
> the discrepancy and based on the discussion, it appears that the divergence
> between the two registries is inadvertent.   Jonathan and I took the action
> item to consult with IANA to explore ways we could address the divergence.
>
>
>
> I have sent an email to IANA relating to the registries and will report
> back to the WG at IETF 118 about potential options for addressing the
> divergence.
>
>
>
> Notes
>
> --------
>
>
>
> The VP8 RTP payload format (RFC 7741) Media-type Section 6.1 references
> both the RFC 6838 Mime-type registration template as well as the RFC 4855
> RTP payload format registration, yet VP8 was only registered in the
> Mime-type registry.
>
>
>
> The VP9 RTP payload format (
> https://datatracker.ietf.org/doc/draft-ietf-payload-vp9/) Media-Type
> Section 7 references both RFC 6838 and RFC 4855.  VP9 was registered in
> both registries.
>
>
>
> The HEVC RTP payload format (RFC 7798) Media-type Section 7.1 mentions
> only that "The media subtype for the HEVC codec is allocated from the
> IETF tree" which would appear to refer to the MIME-type registry. It was
> registered only in the MIME-type registry.
>
>
>
> The VVC RTP payload format (RFC 9328) Media-type Section 7.1 does not
> include an explicit indication of which registry to use for the
> registration. It was registered only in the MIME-type registry.
>
>
>
> The AV1 RTP payload format Media-type Section 7.1 (
> https://aomediacodec.github.io/av1-rtp-spec/#71-media-type-definition
> <https://protect2.fireeye.com/v1/url?k=31323334-501cfaf3-313273af-454445554331-0fe18ba921df50fe&q=1&e=bcb5dc8f-c55e-46ea-a97e-9f83e105e745&u=https%3A%2F%2Faomediacodec.github.io%2Fav1-rtp-spec%2F%2371-media-type-definition>)
> refers explicitly to the MIME-type registry (
> https://www.iana.org/assignments/media-types/video/AV1 ) It was
> registered only in the MIME-type registry.
>
>
>
> The EVC RTP payload format (draft-ietf-avtcore-rtp-evc) Media-type Section
> 7.1 does not include an explicit indication of which registry to use for
> the registration.  Should we add a reference to RFC 4855 so as to indicate
> that it should be registered in both the RTP payload format and MIME-type
> registries?
>
>
>
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